Arterioles: The smallest divisions of the arteries located between the muscular arteries and the capillaries.Pia Mater: The innermost layer of the three meninges covering the brain and spinal cord. It is the fine vascular membrane that lies under the ARACHNOID and the DURA MATER.Vasodilation: The physiological widening of BLOOD VESSELS by relaxing the underlying VASCULAR SMOOTH MUSCLE.Venules: The minute vessels that collect blood from the capillary plexuses and join together to form veins.Retinal Artery: Central retinal artery and its branches. It arises from the ophthalmic artery, pierces the optic nerve and runs through its center, enters the eye through the porus opticus and branches to supply the retina.Vasoconstriction: The physiological narrowing of BLOOD VESSELS by contraction of the VASCULAR SMOOTH MUSCLE.Mycotoxicosis: Poisoning caused by the ingestion of mycotoxins (toxins of fungal origin).Vasodilator Agents: Drugs used to cause dilation of the blood vessels.Muscle, Smooth, Vascular: The nonstriated involuntary muscle tissue of blood vessels.Cheek: The part of the face that is below the eye and to the side of the nose and mouth.Nitric Oxide: A free radical gas produced endogenously by a variety of mammalian cells, synthesized from ARGININE by NITRIC OXIDE SYNTHASE. Nitric oxide is one of the ENDOTHELIUM-DEPENDENT RELAXING FACTORS released by the vascular endothelium and mediates VASODILATION. It also inhibits platelet aggregation, induces disaggregation of aggregated platelets, and inhibits platelet adhesion to the vascular endothelium. Nitric oxide activates cytosolic GUANYLATE CYCLASE and thus elevates intracellular levels of CYCLIC GMP.Endothelium, Vascular: Single pavement layer of cells which line the luminal surface of the entire vascular system and regulate the transport of macromolecules and blood components.Juxtaglomerular Apparatus: A complex of cells consisting of juxtaglomerular cells, extraglomerular mesangium lacis cells, the macula densa of the distal convoluted tubule, and granular epithelial peripolar cells. Juxtaglomerular cells are modified SMOOTH MUSCLE CELLS found in the walls of afferent glomerular arterioles and sometimes the efferent arterioles. Extraglomerular mesangium lacis cells are located in the angle between the afferent and efferent glomerular arterioles. Granular epithelial peripolar cells are located at the angle of reflection of the parietal to visceral angle of the renal corpuscle.Microscopy, Video: Microscopy in which television cameras are used to brighten magnified images that are otherwise too dark to be seen with the naked eye. It is used frequently in TELEPATHOLOGY.Vasomotor System: The neural systems which act on VASCULAR SMOOTH MUSCLE to control blood vessel diameter. The major neural control is through the sympathetic nervous system.Vasoconstrictor Agents: Drugs used to cause constriction of the blood vessels.Rats, Sprague-Dawley: A strain of albino rat used widely for experimental purposes because of its calmness and ease of handling. It was developed by the Sprague-Dawley Animal Company.Capillaries: The minute vessels that connect the arterioles and venules.Acetylcholine: A neurotransmitter found at neuromuscular junctions, autonomic ganglia, parasympathetic effector junctions, a subset of sympathetic effector junctions, and at many sites in the central nervous system.Nitroarginine: An inhibitor of nitric oxide synthetase which has been shown to prevent glutamate toxicity. Nitroarginine has been experimentally tested for its ability to prevent ammonia toxicity and ammonia-induced alterations in brain energy and ammonia metabolites. (Neurochem Res 1995:200(4):451-6)Cerebral Arteries: The arterial blood vessels supplying the CEREBRUM.Nitroprusside: A powerful vasodilator used in emergencies to lower blood pressure or to improve cardiac function. It is also an indicator for free sulfhydryl groups in proteins.Mesoporphyrins: Porphyrins with four methyl, two ethyl, and two propionic acid side chains attached to the pyrrole rings.NG-Nitroarginine Methyl Ester: A non-selective inhibitor of nitric oxide synthase. It has been used experimentally to induce hypertension.Regional Blood Flow: The flow of BLOOD through or around an organ or region of the body.Renal Circulation: The circulation of the BLOOD through the vessels of the KIDNEY.Coronary Vessels: The veins and arteries of the HEART.Arteries: The vessels carrying blood away from the heart.Nitric Oxide Synthase: An NADPH-dependent enzyme that catalyzes the conversion of L-ARGININE and OXYGEN to produce CITRULLINE and NITRIC OXIDE.Swine, Miniature: Genetically developed small pigs for use in biomedical research. There are several strains - Yucatan miniature, Sinclair miniature, and Minnesota miniature.Vascular Resistance: The force that opposes the flow of BLOOD through a vascular bed. It is equal to the difference in BLOOD PRESSURE across the vascular bed divided by the CARDIAC OUTPUT.Blood Pressure: PRESSURE of the BLOOD on the ARTERIES and other BLOOD VESSELS.Enzyme Inhibitors: Compounds or agents that combine with an enzyme in such a manner as to prevent the normal substrate-enzyme combination and the catalytic reaction.Mesocricetus: A genus of the family Muridae having three species. The present domesticated strains were developed from individuals brought from Syria. They are widely used in biomedical research.Muscle, Skeletal: A subtype of striated muscle, attached by TENDONS to the SKELETON. Skeletal muscles are innervated and their movement can be consciously controlled. They are also called voluntary muscles.Hydronephrosis: Abnormal enlargement or swelling of a KIDNEY due to dilation of the KIDNEY CALICES and the KIDNEY PELVIS. It is often associated with obstruction of the URETER or chronic kidney diseases that prevents normal drainage of urine into the URINARY BLADDER.Retinal Vessels: The blood vessels which supply and drain the RETINA.Nitric Oxide Synthase Type III: A CALCIUM-dependent, constitutively-expressed form of nitric oxide synthase found primarily in ENDOTHELIAL CELLS.Kidney Glomerulus: A cluster of convoluted capillaries beginning at each nephric tubule in the kidney and held together by connective tissue.Adenosine: A nucleoside that is composed of ADENINE and D-RIBOSE. Adenosine or adenosine derivatives play many important biological roles in addition to being components of DNA and RNA. Adenosine itself is a neurotransmitter.Muscle Tonus: The state of activity or tension of a muscle beyond that related to its physical properties, that is, its active resistance to stretch. In skeletal muscle, tonus is dependent upon efferent innervation. (Stedman, 25th ed)Indomethacin: A non-steroidal anti-inflammatory agent (NSAID) that inhibits the enzyme cyclooxygenase necessary for the formation of prostaglandins and other autacoids. It also inhibits the motility of polymorphonuclear leukocytes.Rats, Inbred WKY: A strain of Rattus norvegicus used as a normotensive control for the spontaneous hypertensive rats (SHR).Rats, Inbred SHR: A strain of Rattus norvegicus with elevated blood pressure used as a model for studying hypertension and stroke.Norepinephrine: Precursor of epinephrine that is secreted by the adrenal medulla and is a widespread central and autonomic neurotransmitter. Norepinephrine is the principal transmitter of most postganglionic sympathetic fibers and of the diffuse projection system in the brain arising from the locus ceruleus. It is also found in plants and is used pharmacologically as a sympathomimetic.Swine: Any of various animals that constitute the family Suidae and comprise stout-bodied, short-legged omnivorous mammals with thick skin, usually covered with coarse bristles, a rather long mobile snout, and small tail. Included are the genera Babyrousa, Phacochoerus (wart hogs), and Sus, the latter containing the domestic pig (see SUS SCROFA).Dose-Response Relationship, Drug: The relationship between the dose of an administered drug and the response of the organism to the drug.Blood Flow Velocity: A value equal to the total volume flow divided by the cross-sectional area of the vascular bed.Kidney: Body organ that filters blood for the secretion of URINE and that regulates ion concentrations.Potassium Chloride: A white crystal or crystalline powder used in BUFFERS; FERTILIZERS; and EXPLOSIVES. It can be used to replenish ELECTROLYTES and restore WATER-ELECTROLYTE BALANCE in treating HYPOKALEMIA.Rats, Wistar: A strain of albino rat developed at the Wistar Institute that has spread widely at other institutions. This has markedly diluted the original strain.Bradykinin: A nonapeptide messenger that is enzymatically produced from KALLIDIN in the blood where it is a potent but short-lived agent of arteriolar dilation and increased capillary permeability. Bradykinin is also released from MAST CELLS during asthma attacks, from gut walls as a gastrointestinal vasodilator, from damaged tissues as a pain signal, and may be a neurotransmitter.Hydrazines15-Hydroxy-11 alpha,9 alpha-(epoxymethano)prosta-5,13-dienoic Acid: A stable prostaglandin endoperoxide analog which serves as a thromboxane mimetic. Its actions include mimicking the hydro-osmotic effect of VASOPRESSIN and activation of TYPE C PHOSPHOLIPASES. (From J Pharmacol Exp Ther 1983;224(1): 108-117; Biochem J 1984;222(1):103-110)Microvessels: The finer blood vessels of the vasculature that are generally less than 100 microns in internal diameter.Angiotensin II: An octapeptide that is a potent but labile vasoconstrictor. It is produced from angiotensin I after the removal of two amino acids at the C-terminal by ANGIOTENSIN CONVERTING ENZYME. The amino acid in position 5 varies in different species. To block VASOCONSTRICTION and HYPERTENSION effect of angiotensin II, patients are often treated with ACE INHIBITORS or with ANGIOTENSIN II TYPE 1 RECEPTOR BLOCKERS.Retinal Vein: Central retinal vein and its tributaries. It runs a short course within the optic nerve and then leaves and empties into the superior ophthalmic vein or cavernous sinus.Cyclic N-Oxides: Heterocyclic compounds in which an oxygen is attached to a cyclic nitrogen.Cyclooxygenase Inhibitors: Compounds or agents that combine with cyclooxygenase (PROSTAGLANDIN-ENDOPEROXIDE SYNTHASES) and thereby prevent its substrate-enzyme combination with arachidonic acid and the formation of eicosanoids, prostaglandins, and thromboxanes.Prostaglandins: A group of compounds derived from unsaturated 20-carbon fatty acids, primarily arachidonic acid, via the cyclooxygenase pathway. They are extremely potent mediators of a diverse group of physiological processes.Glyburide: An antidiabetic sulfonylurea derivative with actions similar to those of chlorpropamide.Corrosion Casting: A tissue preparation technique that involves the injecting of plastic (acrylates) into blood vessels or other hollow viscera and treating the tissue with a caustic substance. This results in a negative copy or a solid replica of the enclosed space of the tissue that is ready for viewing under a scanning electron microscope.Stress, Mechanical: A purely physical condition which exists within any material because of strain or deformation by external forces or by non-uniform thermal expansion; expressed quantitatively in units of force per unit area.Potassium Channel Blockers: A class of drugs that act by inhibition of potassium efflux through cell membranes. Blockade of potassium channels prolongs the duration of ACTION POTENTIALS. They are used as ANTI-ARRHYTHMIA AGENTS and VASODILATOR AGENTS.Mesentery: A layer of the peritoneum which attaches the abdominal viscera to the ABDOMINAL WALL and conveys their blood vessels and nerves.Pimozide: A diphenylbutylpiperidine that is effective as an antipsychotic agent and as an alternative to HALOPERIDOL for the suppression of vocal and motor tics in patients with Tourette syndrome. Although the precise mechanism of action is unknown, blockade of postsynaptic dopamine receptors has been postulated. (From AMA Drug Evaluations Annual, 1994, p403)Perfusion: Treatment process involving the injection of fluid into an organ or tissue.

Calcium responses induced by acetylcholine in submucosal arterioles of the guinea-pig small intestine. (1/2323)

1. Calcium responses induced by brief stimulation with acetylcholine (ACh) were assessed from the fluorescence changes in fura-2 loaded submucosal arterioles of the guinea-pig small intestine. 2. Initially, 1-1.5 h after loading with fura-2 (fresh tissues), ACh increased [Ca2+]i in a concentration-dependent manner. This response diminished with time, and finally disappeared in 2-3 h (old tissues). 3. Ba2+ elevated [Ca2+]i to a similar extent in both fresh and old tissues. ACh further increased the Ba2+-elevated [Ca2+]i in fresh tissues, but reduced it in old tissues. Responses were not affected by either indomethacin or nitroarginine. 4. In fresh mesenteric arteries, mechanical removal of endothelial cells abolished the ACh-induced increase in [Ca2+]i, with no alteration of [Ca2+]i at rest and during elevation with Ba2+. 5. In the presence of indomethacin and nitroarginine, high-K+ solution elevated [Ca2+]i in both fresh and old tissues. Subsequent addition of ACh further increased [Ca2+]i in fresh tissues without changing it in old tissues. 6. Proadifen, an inhibitor of the enzyme cytochrome P450 mono-oxygenase, inhibited the ACh-induced changes in [Ca2+]i in both fresh and Ba2+-stimulated old tissues. It also inhibited the ACh-induced hyperpolarization. 7. In fresh tissues, the ACh-induced Ca2+ response was not changed by apamin, charybdotoxin (CTX), 4-aminopyridine (4-AP) or glibenclamide. In old tissues in which [Ca2+]i had previously been elevated with Ba2+, the ACh-induced Ca2+ response was inhibited by CTX but not by apamin, 4-AP or glibenclamide. 8. It is concluded that in submucosal arterioles, ACh elevates endothelial [Ca2+]i and reduces muscular [Ca2+]i, probably through the hyperpolarization of endothelial or smooth muscle membrane by activating CTX-sensitive K+ channels.  (+info)

Interaction of amylin with calcitonin gene-related peptide receptors in the microvasculature of the hamster cheek pouch in vivo. (2/2323)

1. This study used intravital microscopy to investigate the receptors stimulated by amylin which shares around 50% sequence homology with the vasodilator calcitonin gene-related peptide (CGRP) in the hamster cheek pouch microvasculature in vivo. 2. Receptor agonists dilated arterioles (diameters 20-40 microm). The -log of the concentrations (+/- s.e.mean; n = 8) causing 50% increase in arteriole diameter were: human betaCGRP (10.8 +/- 0.3), human alphaCGRP (10.8 +/- 0.4), rat alphaCGRP (10.4 +/- 0.3). Rat amylin and the CGRP2 receptor selective agonist [Cys(ACM2,7]-human alphaCGRP were 100 fold less potent (estimates were 8.5 +/- 0.4 and 8.2 +/- 0.3 respectively). 3. The GCRP1 receptor antagonist, CGRP8-37 (300 nmol kg(-1); i.v.) reversibly inhibited the increase in diameter evoked by human alphaCGRP (0.3 nM) from 178 +/- 22% to 59 +/- 12% (n = 8; P < 0.05) and by rat amylin (100 nM) from 138 +/- 23% to 68 +/- 24% (n = 6; P < 0.05). CGRP8-37 did not inhibit vasodilation evoked by substance P (10 nM; n = 4: P > 0.05). 4. The amylin receptor antagonist, amylin8-37 (300 nmol kg(-1); i.v.) did not significantly inhibit the increase in diameter evoked by human alphaCGRP (0.3 nM) which was 112 +/- 26% in the absence, and 90 +/- 29% in the presence of antagonist (n = 4; P < 0.05); nor that evoked by rat amylin (100 nM) which was 146 +/- 23% in the absence and 144 +/- 32% in the presence of antagonist (n = 4; P > 0.05). 5. The agonist profile for vasodilatation and the inhibition of this dilatation by CGRP8-37, although not the amylin8-37 indicates that amylin causes vasodilatation through interaction with CGRP1 receptors in the hamster cheek pouch.  (+info)

Spread of vasodilatation and vasoconstriction along feed arteries and arterioles of hamster skeletal muscle. (3/2323)

1. In arterioles of the hamster cheek pouch, vasodilatation and vasoconstriction can spread via the conduction of electrical signals through gap junctions between cells that comprise the vessel wall. However, conduction in resistance networks supplying other tissues has received relatively little attention. In anaesthetized hamsters, we have investigated the spread of dilatation and constriction along feed arteries and arterioles of the retractor muscle, which is contiguous with the cheek pouch. 2. When released from a micropipette, acetylcholine (ACh) triggered vasodilatation that spread rapidly along feed arteries external to the muscle and arterioles within the muscle. Responses were independent of changes in wall shear rate, perivascular nerve activity, or release of nitric oxide, indicating cell-to-cell conduction. 3. Vasodilatation conducted without decrement along unbranched feed arteries, yet decayed markedly in arteriolar networks. Thus, branching of the conduction pathway dissipated the vasodilatation. 4. Noradrenaline (NA) or a depolarizing KCl stimulus evoked constriction of arterioles and feed arteries of the retractor muscle that was constrained to the vicinity of the micropipette. This behaviour contrasts sharply with the conduction of vasodilatation in these microvessels and with the conduction of vasoconstriction elicited by NA and KCl in cheek pouch arterioles. 5. Focal electrical stimulation produced constriction that spread rapidly along feed arteries and arterioles. These responses were inhibited by tetrodotoxin or prazosin, confirming the release of NA along perivascular sympathetic nerves, which are absent from arterioles studied in the cheek pouch. Thus, sympathetic nerve activity co-ordinated the contraction of smooth muscle cells as effectively as the conduction of vasodilatation co-ordinated their relaxation. 6. In the light of previous findings in the cheek pouch, the properties of vasoconstriction and vasodilatation in feed arteries and arterioles of the retractor muscle indicate that substantive differences can exist in the nature of signal transmission along microvessels of tissues that differ in structure and function.  (+info)

Neovascularization at the vascular pole region in diabetic glomerulopathy. (4/2323)

BACKGROUND: Diabetic nephropathy is associated with renal structural changes involving all of the compartments. Most characteristic is the diabetic glomerulopathy. Studies of the histological changes during the early phases of nephropathy have included the glomerulopathy and also the juxtaglomerular structures. Neovascularization, well-known in diabetic retinopathy, has also been observed in the kidney. The present study concerns estimates of frequency of neovascularization at the vascular pole region in early stages of diabetic nephropathy. METHODS: Extra efferent arterioles at the glomerular vascular pole were detected during measurements of the vascular pole area applying 1-microm serial sections through kidney biopsies. It was observed that more than one efferent arteriole existed occasionally. The present study was carried out with the aim of estimating the frequency of this phenomenon in diabetic patients and in non-diabetic controls, the diabetic patients categorized according to the level of albumin excretion rate. RESULTS: Neovascularization was first observed in IDDM patients with microalbuminuria. Some of the cases presented the phenomenon in all of the glomeruli studied. As the examinations of many kidney biopsies continued the phenomenon was observed also in the non-diabetic control group and in one IDDM patient with normoalbuminuria. However, the frequency was statistically highly significantly increased in patients with elevated albumin-excretion. Within this group a strong correlation between frequency of neovascularization and the severity of diabetic glomerulopathy is seen. CONCLUSIONS: The vascular abnormality localized to the vascular pole region is observed occasionally in the normal kidney, but the frequency is increased in patients with diabetic glomerulopathy. The abnormality may develop as a consequence of a long-standing diabetic glomerulopathy and might lead to less pronounced elevation of albumin excretion.  (+info)

Inhibition of NO synthesis or endothelium removal reveals a vasoconstrictor effect of insulin on isolated arterioles. (5/2323)

In this study we tested the hypothesis that insulin may differentially affect isolated arterioles from red (RGM) and white gastrocnemius muscles (WGM) because of their differences in function and metabolic profile. We also determined whether the responses of these arterioles are endothelium dependent and mediated by either prostaglandins or nitric oxide (NO). Arterioles were isolated, pressurized to 85 mmHg, equilibrated in Krebs bicarbonate-buffered solution (pH 7.4) gassed with 10% O2 (5% CO2-85% N2), and studied in a no-flow state. Control diameters for first-order arterioles from RGM averaged 77 +/- 8 micrometers and from WGM averaged 77 +/- 5 micrometers. Cumulative dose-response curves to insulin (10 microU/ml, 100 microU/ml, 1 mU/ml, and 10 mU/ml) were obtained in arterioles before and after endothelium removal or administration of either indomethacin (Indo, 10(-5) M) or NG-nitro-L-arginine (L-NNA, 10(-4) M). Insulin evoked concentration-dependent increases in control diameter of intact RGM and WGM arterioles of 6-26% and 9-28%, respectively. Indo was without any effect on insulin-induced dilation in RGM and WGM arterioles. Insulin-evoked dilation in both RGM and WGM arterioles was completely inhibited and converted to vasoconstriction by endothelium removal and administration of L-NNA. These results indicate that in endothelium-intact arterioles from RGM and WGM, insulin evokes an endothelium-dependent dilation that is equivalent and mediated by NO. In contrast, in the absence of a functional endothelium, insulin evokes arteriolar constriction. The finding that insulin can constrict arterioles, at physiological concentrations, suggests that insulin may play a more significant role in the regulation of vascular tone and total peripheral resistance than previously appreciated.  (+info)

Conducted signals within arteriolar networks initiated by bioactive amino acids. (6/2323)

Our purpose was to determine the specificity of L-arginine (L-Arg)-induced conducted signals for intra- vs. extracellular actions of L-Arg. Diameter and red blood cell velocities were measured for arterioles [18 +/- 1.6 (SE) micrometer] in the cremaster muscle of pentobarbital sodium-anesthetized (Nembutal, 70 mg/kg) hamsters (n = 53). Remote (conducted) responses were viewed approximately 1,000 micrometer upstream from the local (micropipette) application. Six amino acids were tested: L-arginine, L-cystine, L-leucine, L-lysine, L-histidine, and L-aspartate (100 microM each). Only L-Arg induced a remote dilation; L-lysine and L-aspartate had no effect, and the others each induced a significant remote constriction. There is a second conducted signal initiated by L-arginine that preconditions the arteriolar network and upregulates a direct response of L-arginine to dilate the remote site. This was blocked by inhibition of L-arginine uptake at the local (preconditioning) site (100 microM L-histidine or 1 mM phenformin). Arginine-glycine-aspartate (100 microM)-induced remote dilations (+3. 2 +/- 0.3 micrometer) were not mimicked by a peptide control and were prevented by anti- integrin alphav monoclonal antibody. Remote dilations were greater in animals with a higher wall shear stress for arginine-glycine-aspartate (r2 = 0.92) but not for L-arginine (r2 = 0.12). Thus L-arginine initiates separate conducted signals related to system y+ transport, integrins, and baseline flow.  (+info)

Endothelin antagonists block alpha1-adrenergic constriction of coronary arterioles. (7/2323)

We have previously observed that intracoronary administration of the alpha1-adrenergic agonist phenylephrine (PE) over a period of minutes induced both an immediate and long-lasting (2 h) vasoconstriction of epicardial coronary arterioles. Because it is unlikely that alpha1-adrenergic constriction would persist for hours after removal of the agonist, this observation supports the view that another constrictor(s) is released during alpha1-adrenergic activation and induces the prolonged vasoconstriction. Therefore, we hypothesized that the prolonged microvascular constriction after PE is due to the production of endothelin (ET). We focused on ET not only because this peptide produces potent vasoconstriction but also because its vasoconstrictor action is characterized by a long duration. To test this hypothesis, the diameters of coronary arterioles (<222 micrometers) in the beating heart of pentobarbital-anesthetized dogs with stroboscopic intravital microscopy were measured during a 15-min intracoronary infusion of PE (1 microgram. kg-1 . min-1) and at 15-min intervals for a total of 120 min. All experiments were performed in the presence of beta-adrenergic blockade with propranolol. At 120 min, arterioles in the PE group were constricted (-23 +/- 9% change in diameter vs. baseline). Pretreatment with the ET-converting enzyme inhibitor phosphoramidon or the ETA-receptor antagonist FR-139317 prevented the PE-induced constriction at 120 min (-1 +/- 3 and -6 +/- 3%, respectively, P < 0.01 vs. PE). Pretreatment with the selective alpha1-adrenergic antagonist prazosin (Prz) also prevented the sustained constriction (0 +/- 2%, P < 0.01 vs. PE) but Prz given 60 min after PE infusion did not (-13 +/- 3%). In the aggregate, these results show that vasoconstriction of epicardial coronary arterioles via alpha1-adrenergic activation is blocked by an ET antagonist and an inhibitor of its production. From these data, we conclude that alpha1-adrenergic activation promotes the production and/or release of ET, which produces or facilitates microvascular constriction of epicardial canine coronary arterioles.  (+info)

Flow regulation of ecNOS and Cu/Zn SOD mRNA expression in porcine coronary arterioles. (8/2323)

The purpose of this study was to test the hypothesis that increased flow through coronary arterioles increases endothelial cell nitric oxide synthase (ecNOS) and Cu/Zn superoxide dismutase (SOD) mRNA expression. Single porcine coronary arterioles (ID 100-160 micrometers; pressurized) were cannulated, perfused, and exposed to intraluminal flow sufficient to produce maximal flow-induced dilation of coronary arterioles (high flow; 7.52 +/- 0.22 microliter/min), low flow (0.84 +/- 0.05 microliter/min), or no flow for 2 or 4 h. Mean shear stress was calculated to be 5.7 +/- 1.0 dyn/cm2 for high-flow arterioles and 1. 6 +/- 1.0 dyn/cm2 for low-flow arterioles. At the end of the treatment period, mRNA was isolated from each vessel, and ecNOS and SOD mRNA expression was assessed using a semiquantitative RT-PCR. All data were standardized by coamplifying ecNOS or SOD with glyceraldehyde-3-phosphate dehydrogenase. The results indicate that ecNOS mRNA expression is increased in arterioles exposed to 2 or 4 h of high flow. In contrast, SOD mRNA expression was increased only after 4 h of high flow. Neither gene is induced by exposure to low flow. On the basis of these data, we concluded that ecNOS and SOD mRNA expression is regulated by flow in porcine coronary arterioles. In addition, we concluded that a threshold level of flow and shear stress must be sustained to elicit the upregulation of ecNOS and SOD mRNA expression.  (+info)

*Afferent arterioles

The afferent arterioles branch from the renal artery, which supplies blood to the kidneys. The afferent arterioles later ... The afferent arterioles are a group of blood vessels that supply the nephrons in many excretory systems. They play an important ... If the afferent arterioles are constricted then the blood pressure in the capillaries of the kidneys will drop. Efferent ... The macula densa cell can also increase the blood pressure of the afferent arterioles by decreasing the synthesis of adenosine ...

*Straight arterioles of kidney

Each straight arteriole has a hairpin turn in the medulla and carries blood at a very slow rate - two factors crucial in the ... The straight arterioles are peritubular capillaries, specifically those that surround the loop of Henle. On a histological ... On the descending portion of the straight arterioles, NaCl and urea are reabsorbed into the blood, while water is secreted. On ... For the intestinal structure, see Vasa recta (intestines) In the blood supply of the kidney, the straight arterioles of kidney ...

*Arteriole

Pulmonary arterioles are a noteworthy exception as they vasodilate in response to high oxygen. Brain arterioles are ... An arteriole is a small-diameter blood vessel in the microcirculation that extends and branches out from an artery and leads to ... Arterioles have muscular walls (usually only one to two layers of smooth muscle) and are the primary site of vascular ... Arterioles receive autonomic nervous system innervation and respond to various circulating hormones in order to regulate their ...

*Efferent arteriole

The efferent arterioles are blood vessels that are part of the urinary tract of organisms. Efferent (from Latin ex + facere) ... The efferent arterioles form from a convergence of the capillaries of the glomerulus, and carry blood away from the glomerulus ... The efferent arterioles of the juxtamedullary glomeruli are much different. They do break up, but they form bundles of vessels ... The efferent arterioles of the undifferentiated cortical glomeruli are the most complex. Promptly on leaving the glomerulus ...

*Endometrial stromal sarcoma

Prominent arterioles. Angiolymphatic invasion common. Up to 10-15 mitotic figures per 10 HPF in most active areas. Tongue-like ...

*Cannon-Bard theory

... contraction of arterioles; dilatation of bronchioles; increased levels of blood sugar; sweating; widening of the pupils and ...

*Beta-2 adrenergic receptor

Dilate arterioles to skeletal muscle. In the normal eye, beta-2 stimulation by salbutamol increases intraocular pressure via ...

*Necrotizing vasculitis

Affects capillaries, venules, or arterioles. Thought to be part of a group that includes granulomatosis with polyangiitis since ... or arterioles. Therefore, complement will be low with histology showing vessel inflammation with immune deposits. Vasculitis ... including venules and arterioles. Produces granulomatous inflammation of the respiratory tracts and necrotizing, pauci-immune ...

*Hemodynamics

Immediately following the arterioles are the capillaries. Following the logic observed in the arterioles, we expect the blood ... This is why[citation needed] the arterioles have the highest pressure-drop. The pressure drop of the arterioles is the product ... In the arterioles blood pressure is lower than in the major arteries. This is due to bifurcations, which cause a drop in ... The high resistance observed in the arterioles, which factor largely in the ∆P is a result of a smaller radius of about 30 µm. ...

*Robert Hollenhorst

"Significance of bright plaques in the retinal arterioles". JAMA. 178: 23-29. doi:10.1001/jama.1961.03040400025005. PMID ...

*Erythromelalgia

ICD-10-CM Diagnosis Codes > Diseases of the circulatory system (I00-I99) > Diseases of arteries, arterioles and capillaries ( ... ICD-9-CM Diagnosis Codes > Diseases of the circulatory system (390-459) > Diseases of arteries, arterioles, and capillaries ( ...

*Hollenhorst plaque

N Hollenhorst RW (1961). "Significance of bright plaques in the retinal arterioles". Jama 1961. 178: 23-29. doi:10.1001/jama. ...

*Conjunctiva

In some subjects, arterioles and venules can be seen to run parallel with each other. Paired arterioles are generally smaller ... The bulbar conjunctival microvasculature contains arterioles, meta-arterioles, venules, capillaries, and communicating vessels ... Hypertension is associated with an increase in the tortuosity of bulbar conjunctival blood vessels and capillary and arteriole ...

*Arteriolar vasodilator

... s are substances that preferentially dilate arterioles. When used on people with certain heart conditions ...

*Tubuloglomerular feedback

Efferent arterioles appear to play a lesser role; experimental evidence supports both vasoconstriction and vasodilation, with ... The muscle tension in the afferent arteriole is modified based on the difference between the sensed concentration and a target ... Constricting the smooth muscle cells in the afferent arteriole, results in a reduced concentration of chloride at the MD. TGF ... Adenosine constricts the afferent arteriole by binding with high affinity to the A1 receptors a Gi/Go. Adenosine binds with ...

*Vascular resistance

Another determinant of vascular resistance is the pre-capillary arterioles. These arterioles are less than 100 µm in diameter. ... Because resistance is inversely proportional to the fourth power of vessel radius, changes to arteriole diameter can result in ... The major determinant of vascular resistance is small arteriolar (known as resistance arterioles) tone. These vessels are from ... Adenosine causes vasodilation in the small and medium-sized resistance arterioles (less than 100 µm in diameter). When ...

*Nonsteroidal anti-inflammatory drug

... angiotensin II also constricts the afferent arteriole into the glomerulus in addition to the efferent arteriole it normally ... Prostaglandins normally dilate the afferent arterioles of the glomeruli. This helps maintain normal glomerular perfusion and ... Since NSAIDs block this prostaglandin-mediated effect of afferent arteriole dilation, particularly in kidney failure, NSAIDs ... which removes angiotensin II's vasoconstriction of the efferent arteriole) and a diuretic (which drops plasma volume, and ...

*Myogenic mechanism

The myogenic mechanism is how arteries and arterioles react to an increase or decrease of blood pressure to keep the blood flow ... This is especially relevant in arterioles of the body. When blood pressure is increased in the blood vessels and the blood ...

*Renovascular hypertension

... located on the afferent arteriole wall). This leads to renin secretion that causes the angiotensinogen conversion to ...

*Venule

The middle layer is poorly developed so that venules have thinner walls than arterioles. They are extremely porous so that ... Arteriole Woods, Susan (2010). Cardiac Nursing. New York: Lippincotts. p. 955. ISBN 9780781792806. MeSH A07.231.432.952. ... the blood stream and enter the lymph nodes via these specialized venules when an infection is detected.Compared with arterioles ...

*Spleen

The germinal centers are supplied by arterioles called penicilliary radicles. The spleen is unique in respect to its ...

*Biofluid dynamics

Arteries, arterioles, capillaries, venules, and veins make up the vasculature. The cardiovascular system circulates about 5 ... circulations take the blood through large arteries first and then branches into smaller arteries before reaching arterioles and ...

*Resistance artery

Human arteries or arterioles that are around 0.2 mm or smaller contribute to creation of the blood flow resistance and are ... Resistance arteries are usually arterioles or end-points of arteries. Having thick muscular walls and narrow lumen they ... arterioles, pre- and postcapillaries. Metabolic vessels - capillaries Capacitance vessels - veins Particular feature of ... Arteriole Cardiovascular Physiology By William R. Milnor. ...

*Artery

... down to the arterioles. The arterioles supply capillaries, which in turn empty into venules. The very first branches off of the ... Arterioles have the greatest collective influence on both local blood flow and on overall blood pressure. They are the primary ... Arterioles help in regulating blood pressure by the variable contraction of the smooth muscle of their walls, and deliver blood ... Systemic arteries deliver blood to the arterioles, and then to the capillaries, where nutrients and gases are exchanged. After ...

*Trabecular arteries

The arterioles end by opening freely into the splenic pulp; their walls become much attenuated, they lose their tubular ... The arterioles, supported by the minute trabeculae, traverse the pulp in all directions in bundles (penicilli) of straight ... The altered coat of the arterioles, consisting of adenoid tissue, presents here and there thickenings of a spheroidal shape, ... or central arterioles). Branches of the central arteries are given to the red pulp, and these are called penicillar arteries). ...
We performed experiments to test the hypothesis that endogenous adenosine acts as an essential cofactor required for eliciting angiotensin II (Ang II)-induced afferent and/or efferent arteriolar vasoconstriction. Enalaprilat (2 mg IV) was administered to anesthetized rats to reduce endogenous Ang II levels. Kidneys and blood were harvested from these animals and used for study of renal microvascular function using the in vitro blood-perfused juxtamedullary nephron technique. Arteriolar inside diameter was monitored videomicroscopically in (1) normal kidneys, (2) kidneys subjected to adenosine receptor blockade (100 mumol/L 1,3-dipropyl-8-p-sulfophenylxanthine), and (3) kidneys continuously exposed to 1 mumol/L adenosine. Under resting conditions, arteriolar diameters were similar in all three groups of kidneys, averaging 24.8 +/- 1.0 microns (n = 23) in afferent arterioles and 24.0 +/- 0.9 microns (n = 16) in efferent arterioles. In normal kidneys, adenosine (10 mumol/L) decreased both afferent ...
The major finding of the present study is that selective intrarenal nNOS inhibition by L-SMTC elicited marked decreases in renal hemodynamics and sodium excretory functions in normotensive rats and did not significantly influence renal function in Ang II-infused hypertensive rats. This finding is in a good agreement with the previous studies demonstrating an important role for nNOS in buffering TGF-mediated afferent arteriolar vasoconstriction in normotensive rats.9-11 In line with our finding is also the recent observation made by Ichihara et al13 employing the in vitro blood-perfused juxtamedullary nephron preparation that the decrease in afferent arteriolar diameter in response to L-SMTC administration was significantly less in Ang II-infused rats compared with control rats.. It has been also shown that nNOS activity, nNOS mRNA, and renin mRNA are increased in AT1A receptor gene and angiotensinogen gene knockout mice.18,19 In addition, studies evaluating the effects of sodium intake on renin, ...
TY - JOUR. T1 - Vascular Endothelium and Smooth Muscle Remodeling Accompanies Hypertrophy of Intestinal Arterioles in Streptozotocin Diabetic Rats. AU - Connors, Bret A.. AU - Bohlen, H.. AU - Evan, Andrew. PY - 1995/5. Y1 - 1995/5. N2 - The purpose of this study was to document alterations in endothelial and smooth muscle cell morphology of first- and second-order intestinal arterioles after 6 months of streptozotocin-induced diabetes. Both light and scanning electron microscopic techniques were used to quantitate the changes in the microvasculature. After rendering the first- and second-order intestinal arterioles passive and processing the vessels, it was determined that these microvessels were significantly dilated in the diabetic animals. Further examination revealed that in the diabetic animals, the cross-sectional area of the endothelial layer was increased in both 1A and 2A vessels, and the smooth muscle layer cross-sectional area was significantly increased in 1A vessels. Individual ...
Aims: To study the effect of an acute increase in the arterial blood pressure on the diameter response of retinal arterioles supplying areas with focal diabetic macular oedema before and after laser photocoagulation, and control arterioles supplying areas without oedema.. Methods: In 17 diabetic patients the diameter response of arterioles after an increase in the arterial blood pressure induced by isometric exercise was studied using the retinal vessel analyser (RVA). In each patient a study arteriole supplying a focal area of macular oedema as well as a control arteriole supplying a retinal area without retinopathy lesions was selected, and the diameter response of these vessels was performed immediately before, and 1 hour and 3 months after focal laser photocoagulation of the focal oedema area.. Results: The diameter response was impaired in both study arterioles and control arterioles before focal laser photocoagulation. The treatment induced regression of the focal retinal oedema, but did ...
The present study is the first to demonstrate that Ang II activates differing Ca2+ entry mechanisms in afferent and efferent arterioles. Our findings are thus consistent with evolving concepts concerning the segmental heterogeneity of activation mechanisms within the renal microvasculature. In the afferent arteriole, Ang II stimulates Ca2+ influx via dihydropyridine-sensitive and voltage-activated L-type Ca2+ channels, an activating mechanism that is absent in the efferent arteriole. In the efferent arteriole, Ang II stimulates Ca2+ influx through a signaling pathway that is nifedipine-insensitive and is not voltage-activated. Store depletion with CPA activates a nifedipine-insensitive Ca2+ entry in efferent myocytes that has a sensitivity to SKF 96365 identical to that of the Ca2+ influx activated by Ang II in the intact arteriole. This store-operated Ca2+ entry mechanism is absent in the afferent arteriole.. Our findings agree with those of previous studies assessing renal microvascular ...
Purpose: : Hyperglycemia and oxidative stress are implicated in retinal vascular dysfunction associated with the development of diabetic retinopathy. Although retinal arterioles provide a major site of flow regulation, the temporal influence of hyperglycemia on retinal arteriolar reactivity and vascular oxidant production remains unclear. The development of a large animal model of diabetes relevant to the human retina for evaluation of vascular function is also lacking. Herein, we examined endothelium-dependent nitric oxide (NO)-mediated dilation and production of superoxide in retinal arterioles at various time points in a porcine model of type 1 diabetes. Methods: : Retinal arterioles (,100 µm) were isolated from streptozotocin-induced diabetic pigs (2, 6, 10 and 14 weeks of hyperglycemia, 477±43 mg/dL) and age-matched control pigs (63±14 mg/dL), and then cannulated and pressurized for in vitro study. Vascular diameter changes and superoxide production were monitored using videomicroscopic ...
Parenchymal arterioles (PAs) are high-resistance vessels in the brain that connect pial vessels to the microcirculation. We previously showed that PAs have increased vasoconstriction after ischemia and reperfusion that could increase perfusion defici
Flow-induced dilation of human coronary arterioles (HCA) is mediated by a unique mechanism involving the release of H2O2 from the mitochondria of endothelial cells and subsequent smooth muscle relaxation via K+-channel-dependent membrane hyperpolarization. The precise mechanisms by which H2O2 induces smooth muscle hyperpolarization remain largely undefined. An important mechanism of action of H2O2 involves the oxidation of key cysteine residues in its target proteins, including protein kinase G 1-alpha (PKG-1α). Here we hypothesize that H2O2 dilates HCA through direct oxidation and activation of PKG-1α leading to the subsequent opening of large-conductance Ca2+-activated K+ channels (BKCa) in smooth muscle cells. In isolated HCA, H2O2 (10−6−3×10−4 M) induced dose-dependent dilations in both endothelium-intact and -denuded vessels (relaxations at 10−4 M of 83.5±3.7% and 85.1±8.4%, respectively; n=4 - 6). The relaxations were largely abolished by iberiotoxin, a BKCa blocker (3.4±2.1% ...
We used a lung slice preparation to study the contractile responses of intrapulmonary arterioles and the underlying changes in [Ca2+]i in their SMCs during stimulation with 5-HT and KCl. For the same reasons that apply to the study of bronchial airways (Bergner and Sanderson, 2002a), thin lung slices are well suited for the study of arterioles. The arterioles are easily identified, have reproducible contractile responses and the intracellular Ca2+ responses of their SMCs can be correlated with the contraction of the arteriole. In addition, the small intrapulmonary arterioles, at sites that are considered to be important in pulmonary hypertension, can be examined. A major advantage of the lung slice is the ability to simultaneously compare the responses of arteriole SMCs to those of airway SMCs. This allows for the instant collection of control data and facilitates an understanding of the specific physiological responses of each SMC type.. Vasoconstriction of pulmonary arteries to 5-HT has been ...
It is typical in microvascular networks for smaller vessels to have lower linear blood velocities (38, 67). Application of a LEA instrument to vessels with velocities below Vcr = 2,100 μm/s creates a progressive Po2 underestimation from large arterioles to capillaries due to an increase in the accumulated oxygen consumption with the decrease in velocity. In addition, a LEA instrument depresses Po2 in the perivascular tissue (16), thereby creating a greater oxygen sink, which adds to the diffusional oxygen losses from arterioles and amplifies the apparent longitudinal Po2 gradient. Previous workers have concluded that this apparent longitudinal Po2 gradient found in precapillary arterioles is due to high oxygen losses from the arterioles, which led them to further conclude that arterioles are the main site of oxygen supply to the tissue (52-54, 56).. In the study of Tsai et al. (54), the longitudinal oxygen saturation drop in mesenteric arterioles with an average diameter of 23 μm was estimated ...
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A Human Arteriole Cross-Section. Arterioles are Small Branches of Arteries Photographic Print by Robert Caughey - at AllPosters.com. Choose from over 500,000 Posters & Art Prints. Value Framing, Fast Delivery, 100% Satisfaction Guarantee.
Renal preglomerular arterioles regulate vascular tone to ensure a large pressure gradient over short distances, a function that is extremely important for maintaining renal microcirculation. Regulation of renal microvascular tone is impaired in salt-sensitive (SS) hypertension-induced nephropathy, but the molecular mechanisms contributing to this impairment remain elusive. Here, we assessed the contribution of the SH2 adaptor protein p66Shc (encoded by Shc1) in regulating renal vascular tone and the development of renal vascular dysfunction associated with hypertension-induced nephropathy. We generated a panel of mutant rat strains in which specific modifications of Shc1 were introduced into the Dahl SS rats. In SS rats, overexpression of p66Shc was linked to increased renal damage. Conversely, deletion of p66Shc from these rats restored the myogenic responsiveness of renal preglomerular arterioles ex vivo and promoted cellular contraction in primary vascular smooth muscle cells (SMCs) that were ...
We have formulated a mathematical model for the rat afferent arteriole (AA). Our model consists of a series of arteriolar smooth muscle cells and endothelial cells, each of which represents ion transport, cell membrane potential, and gap junction coupling. Cellular contraction and wall mechanics are also represented for the smooth muscle cells. Blood flow through the AA lumen is described by Poiseuille flow. The AA models representation of the myogenic response is based on the hypothesis that changes in hydrostatic pressure induce changes in the activity of nonselective cation channels. The resulting changes in membrane potential then affect calcium influx through changes in the activity of the voltage-gated calcium channels, so that vessel diameter decreases with increasing pressure values. With this configuration, the model AA maintains roughly stable renal blood flow within a physiologic range of blood flow pressure. Model simulation of vasoconstriction initiated from local stimulation also ...
Aging with oxidant stress is a major risk factor of coronary artery disease, however the underlying mechanisms have not been fully defined. Senescence marker protein 30 (SMP30) has been identified as an aging marker molecule, which decreases with aging and SMP 30 knock-out mice show a short life. To examine the effect of aging on coronary arterioles vasomotor tone, we measured endothelium-dependent (acetylcholine, ACh) and -independent vasodilation (sodium nitroprusside, SNP) of isolated, pressurized coronary arterioles (28±4 µm, diameter) from SMP30 KO and wild type (WT) mice. In SMP30 KO mice, ACh-induced vasoconstriction was appeared, which changed vasodilation with dithiothreitol, thiol-reducing agent (DTT, 0.1 µM), but L-NAME (0.3 mM) or sepiapterin (1 µM), tetrahydrobiopterin mimic, did not change vascular responses to ACh. In WT mice, ACh-induced vasodilation was appeared which was blunted with L-NAME. Inhibition of glutathione reductase by 1, 3-bis (2-chloroethyl)-1-nitrosourea (80 ...
The activity of eNOS can be regulated in part at the post-translational level by acetylation of the enzyme. Accumulating evidence indicates that SIRT1-dependent deacetylation of lysine residues in the calmodulin-binding domain of eNOS leads to increased enzyme activity.41,81 The SIRT1 enzyme is a member of the sirtuin family of nicotinamide adenine dinucleotide-dependent deacetylases, which are involved in regulation of metabolism, stress responses, and senescence.82 In vitro studies have shown that blockade of SIRT1 diminishes endothelium-dependent relaxation of vasculatures.41,83 In addition, exposure of cultured human umbilical vein endothelial cells to laminar shear stress has been shown to promote SIRT1-dependent eNOS deacetylation.81 The present findings underpin the notion that SIRT1 contributes to the transduction of a hemodynamic signal to NO-mediated vasodilation, because selective SIRT1 inhibitor EX52735,84 reduced retinal arteriolar dilation to increased flow. Support for the ...
Role of the Afferent and Efferent Arterioles The kidneys have an autoregulatory system to keep their blood flow and perfusion constant over a wide range of blood pressures. Unlike perfusion of all other organs, perfusion of the kidney is not regulated to maintain organ nutrition but to retain its filtration functions. The glomerular hydrostatic pressure is regulated mainly by the balance of vascular tone in the afferent and efferent arterioles. Owing to this exceptional arrangement of resistance vessels in series, before and after the glomerulus, renal blood flow (RBF) and glomerular filtration rate (GFR) can be regulated independently.
We transplanted neonatal hamster renal tissue into a hamster check pouch chamber and subjected the renal tissue to increases and decreases in extravascular pressure. A decrease in extra-vascular pressure decreased, and an increase in extravascular pressure increased, the diameter of preglomerular arterioles. Thus, the change in preglomerular arteriolar diameter was directly related to alterations in extravascular pressure. Neither saralasin nor indomethacin affected these changes, whereas papaverin prevented them. The efferen arterioles responded passively to changes in extravascular pressure; i.e., the changes in their diameter were inversely related to changes in extravascular myogenic autoregulation of preglomerular vessels. ...
The efferent arteriole carries blood away from the glomerulus. Because it has a smaller diameter than the afferent arteriole, it creates some resistance to blood flow, producing the back-up of blood in the glomerulus which creates higher pressure in the glomerular cavity.. ...
Arteriole. Light micrograph of a section through an arteriole, a small artery. The lumen (centre) of the arteriole is filled with red blood cells. The lumen is lined by a single layer of epithelial cells, which are surrounded by a ring of smooth muscle (purple). Outside of this is elastic and collagen connective tissue (brown). Magnification: x250 when printed at 10 centimetres wide. Human tissue. - Stock Image C019/8018
Chemical: Noradrenaline constricts interlobular and afferent arterioles. Angiotensin 11 constricts efferent arterioles , afferent arterioles. Dopamine (made in kidney) vasodilates. Acetylcholine vasodilates. Prostaglandins inc. bl flow in cortex, dec. bl flow in medulla.. - Neural: SNS -, dec bl flow. Fall of BP, vasoconstrictor response includes renal bl flow.. - Autoregulation: contractile response of smooth muscle of afferent arteriole to stretch (BP). NO may be involved. Angiotensin 11 plays a role in constricting efferent arterioles, maintaining GFR,. ...
Guarda Foto stock di Red And White Blood Cells Within An Arteriole Arteries Branch Into Arterioles Within Organs And Deliver Blood To The Capillaries Sem X6130. Cerca foto premium ad alta risoluzione su Getty Images.
10 μm) the PD cases have fewer capillaries in the RN and more small arterioles/veins (in the LC) with a significant reduction in the ratio of small/large vessels throughout all nuclei. The data suggest that vessel degeneration in PD cases is primarily at the level of capillaries, that may be more vulnerable to degeneration than the small arteries/veins, and/or to the enlarged capillaries as a result of vascular remodelling [6]. The transformation of the microvasculature from primarily capillaries to predominantly small arterioles/venules has a profound effect on oxygen diffusion. Arterioles (and venules) are much larger vessels with, on average, 3 layers of endothelial cells as well as smooth muscle cells and pericytes [7]. In normal tissue the majority of oxygen diffusion occurs from the capillary vessels consisting of only one layer of endothelial cells [7]. As a consequence of the loss of the capillary bed, tissues receive less oxygen leading to damage through processes such as the ...
Prostaglandin F2α constricted pial arterioles when locally applied to the cerebral surface. Norepinephrine and serotonin each elicited similar contractile effects. The constriction produced by F2α in combination with either biogenic amine was greater than the constriction elicited by F2α or amine acting alone. The effect of one agent on the other was additive rather than potentiating. Since F2α, norepinephrine and serotonin are all naturally occurring agents, it is possible that their combined effect is important under pathological circumstances and this combined effect should not be overlooked in the search for single spasmogens of great potency. Before ascribing a pathologically important effect to F2α, either alone or in combination, evidence is required showing that doses effective in experiments are similar to the concentrations occurring during disease states and/or that vessels may become hypersensitive to F2α during such states.. ...
A number of possible explanations may account for the differences between the effects of soluble and insoluble integrin ligands on Ca2+ channel current. An obvious possibility is that inhibition of current by soluble FN may be mediated by competitive antagonism of existing integrin- matrix interactions, as suggested for other systems (Poole and Watson, 1995). This would require constitutive phosphorylation of the channel through an integrin-dependent pathway. Indeed, the L-type calcium channel in vascular smooth muscle has been shown to require tyrosine phosphorylation for normal function (Wijetunge et al., 1992; Wijetunge and Hughes, 1996), but whether integrins regulate this pathway is not known. If they do, then disruption of existing integrin-matrix interactions by soluble ligands would produce inhibition of current while clustering of receptors by insoluble ligands (Altieri et al., 1990; Schwartz, 1993), including antibodies (Miyamoto et al., 1995a), would produce enhancement of current. In ...
Diastolic BP rose and cardiac output diminished after 6 months of exercises training because of the increase in peripheral resistance of blood vessels in athletes. In result of the training, skeletal muscles became capable of a profound relaxation leading, in its turn, to development of the ability for marked constriction of skeletal muscles arterioles. After the exercises, the rigidity of femoral and tibial arteries decreased as the result of involvement of the artery walls smooth muscle cells into peripheral vasodilatation. The functional condition of the skeletal muscles arterioles seems to be the main factor affecting circulatory changes both during acute effect of exercise and after a prolonged training.
Now let us see how the above factors control the distribution of blood flow in physiological situations. The structures that normally have the largest changes in blood flow are the skin, the digestive tract and skeletal muscle.. SKIN: Blood flow to the skin is almost entirely for the purposes of thermoregulation. Very little of the total is required to support the metabolism of the skin cells. Heat is carried by the blood from inside the body to the skin, where it is lost to the atmosphere. Most heat is lost this way, with the only other significant loss of heat occurring through breathing. Sympathetic nerves control the skin arterioles for this purpose, with greater release of norepinephrine causing vasoconstriction. Since under neutral conditions there is some steady sympathetic activity to the skin, reduction of the sympathetic effects allows vasodilation. Unlike many structures, arterioles do not have the dual innervation by both sympathetic and parasympathetic nerves.. DIGESTIVE TRACT: As ...
Arteriole. Coloured transmission electron micrograph (TEM) of a section through the wall of an arteriole, showing smooth muscle (brown), endothelial cells (green), and an inner and outer lamina (membrane, blue). Elastic and collagen connective tissue (clear) can also be seen, along with pinocytotic vesicles.. Magnification: x20,000 when printed 10 centimetres wide. - Stock Image C011/9459
The brain is critically dependent on the regulation of blood flow to nourish active neurons. One widely held hypothesis of blood flow regulation holds that active neurons stimulate Ca(2+) increases in glial cells, triggering glial release of vasodilating agents. This hypothesis has been challenged, as arteriole dilation can occur in the absence of glial Ca(2+) signaling. We address this controversy by imaging glial Ca(2+) signaling and vessel dilation in the mouse retina. We find that sensory stimulation results in Ca(2+) increases in the glial endfeet contacting capillaries, but not arterioles, and that capillary dilations often follow spontaneous Ca(2+) signaling. In IP3R2(-/-) mice, where glial Ca(2+) signaling is reduced, light-evoked capillary, but not arteriole, dilation is abolished. The results show that, independent of arterioles, capillaries actively dilate and regulate blood flow. Furthermore, the results demonstrate that glial Ca(2+) signaling regulates capillary but not arteriole ...
The brain is critically dependent on the regulation of blood flow to nourish active neurons. One widely held hypothesis of blood flow regulation holds that active neurons stimulate Ca(2+) increases in glial cells, triggering glial release of vasodilating agents. This hypothesis has been challenged, as arteriole dilation can occur in the absence of glial Ca(2+) signaling. We address this controversy by imaging glial Ca(2+) signaling and vessel dilation in the mouse retina. We find that sensory stimulation results in Ca(2+) increases in the glial endfeet contacting capillaries, but not arterioles, and that capillary dilations often follow spontaneous Ca(2+) signaling. In IP3R2(-/-) mice, where glial Ca(2+) signaling is reduced, light-evoked capillary, but not arteriole, dilation is abolished. The results show that, independent of arterioles, capillaries actively dilate and regulate blood flow. Furthermore, the results demonstrate that glial Ca(2+) signaling regulates capillary but not arteriole ...
n. a small branch of an artery, leading into many smaller vessels - the capillaries. By their constriction and dilation, under the regulation of the sympathetic nervous system, arterioles are the principal controllers of blood flow and pressure. ...
Arterioles are small, muscular branches of arteries. When they contract, they increase resistance to blood flow, and blood pressure in the arteries goes up.. ...
Arterioles are small, muscular branches of arteries. When they contract, they increase resistance to blood flow, and blood pressure in the arteries goes up.. ...
How does fresh arterial blood make its way through the vast web of tiny vessels in the brain to reach the hungriest neurons? Using live imaging in mice, two studies reveal new elements of neurovascular physiology that play a role. For one, arteriolar endothelial cells were covered with inlets called caveolae, which somehow dictated the dilation and contraction of the vessels. The other identified specialized sphincters that controlled the flow of blood from arterioles into downstream capillary beds.. ...
Last week, Dr. Sanfilippo wrote about our medical students who have been part of research projects and studies. He promised a list of all of our students who have been first authors of studies published or in progress.. Before we bring you to the list, wed like to correct an error in the last blog-two of the articles by students got blended into one in our Excel spreadsheet.. Here are the two separate articles, with apologies to the authors and thanks to Yan Sim for helping us correct this:. Ross GA, Mihok ML, Murrant CL. Extracellular adenosine initiates rapid arteriolar vasodilation induced by a single skeletal muscle contraction in hamster cremaster muscle. Acta Physiol (Oxf) (2013).. and. Sim AY, Hopman W, Engen D, Silva M, James, P. Predicting operative bleeding in elective pediatric surguries using the pediatric bleeding questionnaire. Journal of Pediatric Hematology and Oncology (2013).. And heres the full list as far as we could ascertain from students MSPRs, (Brace yourselves! Its a ...
Blood enters the kidney through the blood vessel called afferent arteriole. The blood is under high pressure. Blood vessels start to bend and twist into and become the glomerulus. The blood then comes out through the blood vessel efferent arteriole in which the diameter of this vessel is smaller and more narrow than the afferent arterioles. The consequence of narrowed vessels is the increase of blood pressure. In other words, the blood pressure increases in the glomerulus. The blood has been filtered due to high pressure because of the smaller area of the blood vessel. The blood has been filtered through undergoing high pressure due to the narrowing glomerulus, which forces in plasma out from the blood into the Bowmans capsule ...
Blood pressure is determined by the force of the heart as it contracts (systole) and the resistance of the main arteries and smaller arteries (called arterioles) to blood ?ow. The other force is diastole or relax- ation. Healthy arterioles are muscular and highly elastic and stretch eas- ily as blood is pumped into them. Their ready squeezing action keeps blood moving. When the heart is pumping more blood, as during exer- cise, many of the arterioles expand to accommodate greater blood ?ow. Healthy arteries are also wide open, clear of any buildup or obstruction so that blood can ?ow freely. Diseased arteries lose their elasticity, and pressure rises.. ...
Glomerular filtration rate (GFR) would be increased by: a) Constriction of the afferent arteriole b) A decrease in afferent arteriolar pressure c) Compression
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Glomerular Filtration Activity 1: Effect of Arteriole Diameter on Glomerular Filtration 1. Compare this data with your baseline data. How did i
Learn about Arterioles, the most highly regulated blood vessels in the body that contribute the most to the rise and fall in systemic blood pressure.
X270 Arteriole Artery Red Blood Cells in Lumen Photographic Print - at AllPosters.com. Choose from over 500,000 Posters & Art Prints. Value Framing, Fast Delivery, 100% Satisfaction Guarantee.
For anybody that missed the Golden Age of arcade games, its sometimes difficult to explain exactly the effect of walking into an arcade with a pocket full of quarters. Row after row of flickering screens. A symphony of beeps and boops competes with Foreigner and Duran Duran being pumped over some tinny speakers. Floors sticky with the residue of dropped Cokes. These palaces were an oasis for gamers -- a stopover escape from the bright world outside where you were not a brave knight, pilot of a space cruiser, or any number of animals that suddenly had the fate of the world hoisted upon on their shoulders. Arcades have largely been ripped from the pop culture landscape. There are a few mega-arcades left in the Gameworks or Dave & Busters chains. The resurgent Chuck E. Cheese offers a modest number of arcade cabinets amongst a sea of redemption games. And every once in a while, you happen upon a retro house that gets by on the strength of thirtysomething nostalgia. However, the hole-in-the-wall
Arcade is about the history of gaming culture. We successively completed Level 1 in November 2010. Seven new interactive gaming installations were made during the Dev Camp, and presented at Sensor Fest. Level 2 is all about video arcade machines and was opened on Saturday December 18, at Mediamatic Bank. Come by anytime before March 27th 2011 to have a go at the games yourself. As for now: the pictures.. ...
The Media Center is closed, however its collections and services are still available. Media Reserves, computers, equipment, and archival collections are available in the Media Arcade. DVD, CD and VHS collections can be checked out from 1st floor Circulati. ...
Press the joystick down to turn your lights on. Push it up to turn them off. BUT THAT'S NOT ALL! See those two red buttons? Press them for super fun arcade sound effects. Entering a room has never been more fun.
The new patch went live quite quickly after hitting the PTR and it brings with it a LOT of changes: Sombra, Arcade Mode, a new map, Competitive ...
The Wanderer has chosen to challenge the Battle Arcade. His first challenge uses the following setup: Sure, Ill take a crack at this. Format: Singles...
Game credits for Puyo Pop Fever (Arcade) database containing game description & game shots, cover art, credits, groups, press, forums, reviews and more.
Introduction The majority of deaths from breast cancer are a total result of metastases; nevertheless, small is definitely recognized about the hereditary modifications root their starting point. had been scored by cell keeping track of, circulation cytometry, and scuff and … Continue reading →. ...
FL-associated STAT6 mutations hyperactivate the IL-4/JAK/STAT6 axis. proved by increased transactivation in HEK293T cellCbased transfection/luciferase reporter assays, heightened interleukin-4 (IL-4) Cinduced activation of target genes in stable STAT6 transfected lymphoma cell lines, and elevated baseline expression amounts of STAT6 focus … Continue reading →. ...
Just two weeks and America will once again be great. Youre gonna be so proud of your president. This is a thread to talk about how great, and how proud.
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He also apparently has low level pain going on a lot of the time after he cracked his head on a concrete floor and started leaking something important from his…
Tämä sivusto käyttää evästeitä analytiikkaan sekä mukautetun sisällön ja mainosten näyttämiseen. Jatkamalla sivuston käyttöä hyväksyt tällaisen käytön. Lisätietoja ...
T cell specificity emerges from a myriad of processes, ranging from the biological pathways that control T cell signaling to the structural and physical mechanisms that influence how TCRs bind peptides and MHC proteins. Of these processes, the binding specificity of the TCR is a key component. However, TCR specificity is enigmatic: TCRs are at once specific but also cross-reactive. Although long appreciated, this duality continues to puzzle immunologists and has implications for the development of TCR-based therapeutics. In this review, we discuss TCR specificity, emphasizing results that have emerged from structural and physical studies of TCR binding. We show how the TCR specificity/cross-reactivity duality can be rationalized from structural and biophysical principles. There is excellent agreement between predictions from these principles and classic predictions about the scope of TCR cross-reactivity. We demonstrate how these same principles can also explain amino acid preferences in ...
Adenomyosis is vastly different from endometriosis (a disorder wherein the endometrial lining of the uterus gets implanted outside the uterus). On the other hand, those having adenomyosis often have endometriosis. Adenomyosis is characterized by severe menstrual cramps and heavy bleeding; and usually disappears after menopause. Although most doctors recommend hysterectomy, there are a host of natural cures and home remedies that help alleviate the symptoms successfully. ...
The major findings in newborn pigs are: (1) treatment with the astrocyte toxin, L-2αAAA, or the HO inhibitor, CrMP, block pial arteriolar dilation to ADP, but not to isoproterenol, bradykinin, or sodium nitroprusside; (2) ADP increases brain CO production and this increase is blocked by the astrocyte toxin or inhibition of HO; and (3) ADP increases CO production by astrocytes and, to a lesser extent, cerebral microvessels. These data, coupled with previous results showing CO dilates pial arterioles in vivo, suggest CO is an astrocyte-derived mediator of ADP-induced pial arteriolar dilation in piglets.. ADP can produce endothelium-dependent cerebral vasodilation,19 which may be mediated in part by NO and endothelium-derived hyperpolarizing factor in adult rats.20,21,30 In endothelium-denuded control arteries from rat brain, ADP also produced dose-dependent relaxation, but this relaxation was lower than that found in intact control arteries.31 In adult rats, ADP-induced pial arteriolar dilation ...
TY - JOUR. T1 - Interaction between ATP-sensitive K+ channels and nitric oxide on pial arterioles in piglets. AU - Bari, F.. AU - Errico, Robert A.. AU - Louis, Thomas M.. AU - Busija, David W.. PY - 1996. Y1 - 1996. N2 - The interaction between ATP-sensitive K+ channels (K(ATP)) and nitric oxide (NO) was studied in pial arterioles of piglets. We examined the effects of N(ω)-nitro-L-arginine methyl ester (L-NAME), a general inhibitor of nitric oxide synthase (NOS), and 7-nitroindazole (7-NI), a selective inhibitor of neuronal NOS, on aprikalim-induced cerebral vasodilation. Topically applied, aprikalim, a selective activator of K(ATP), dilated arterioles by 11 ± 7% at 10-8 M and 17 ± 6% at 10-6 M. After L-NAME treatment (15 mg/kg, i.v.), the response was reduced (4 ± 4% and 12 ± 7%, respectively; n = 8, p ,0.05). Administration of 7-NI (50 mg/kg, i.p.) did not change pial arteriolar responsiveness to aprikalim. However, both L-NAME and 7-NI reduced the vasodilator responses to 10-4 M ...
TY - JOUR. T1 - Responses of cerebral arterioles during chronic ethanol exposure. AU - Mayhan, William. PY - 1992. Y1 - 1992. N2 - The purpose of this study was to examine the effects of ethanol exposure on responses of cerebral arterioles in vivo. Rats were fed liquid diets with or without ethanol for 2-3 mo. Using intravital microscopy, we measured diameter of cerebral arterioles in non-ethanol- and ethanol-fed rats in response to acetylcholine, histamine, ADP, the thromboxane analogue (U- 46619), and nitroglycerin. In non-ethanol-fed rats, acetylcholine, histamine, and ADP produced dose-related dilatation of cerebral arterioles. In ethanol- fed rats, however, acetylcholine produced vasoconstriction, and vasodilatation in response to histamine and ADP was impaired. Dilatation of cerebral arterioles in response to nitroglycerin and vasoconstriction in response to the thromboxane analogue (U-46619) were similar in non-ethanol- fed and ethanol-fed rats. Thus these findings suggest that chronic ...
Subarachnoid hemorrhage (SAH) following cerebral aneurysm rupture is associated with substantial morbidity and mortality. The ability of SAH to induce vasospasm in large diameter pial arteries has been extensively studied, although the contribution of this phenomenon to patient outcome is unclear. Conversely, little is known regarding the impact of SAH on intracerebral (parenchymal) arterioles, which are critical for regulation of cerebral blood flow. To assess the function of parenchymal arterioles following SAH, measurements of diameter, intracellular Ca2+ ([Ca2+]i) and membrane potential were performed in intact arterioles from unoperated (control), sham-operated and SAH model rats. At physiological intravascular pressure, parenchymal arterioles from SAH animals exhibited significantly elevated [Ca2+]i and enhanced constriction compared with arterioles from control and sham-operated animals. Elevated [Ca2+]i and enhanced tone following SAH were observed in the absence of vascular endothelium and were
Blood flow partitioning at an arteriolar bifurcation could lead to spatio-temporal variations in cell-free layer formation in the upstream and downstream vessels of the bifurcation. To investigate this effect, we quantitatively analyzed characteristics of the cell-free layer in the vicinity of an arteriolar bifurcation in the rat cremaster muscle in normal physiological flow conditions. To simulate hemorheological relevance to humans, red blood cell aggregation was elevated by infusion of Dextran 500 to levels seen in humans in normal states. Spatial variations of the layer width were observed in both the parent and larger daughter vessels. A more pronounced attenuation of the layer width was generally observed in the parent vessel at its wall adjacent to the side branch than at its opposite wall. A thicker layer width was consistently found at the opposite than adjacent wall of the larger daughter vessel. Accordingly, large asymmetries of the layer widths could be developed on opposite sides of ...
The vascular myogenic response is characterized by arterial constriction in response to an increase in intraluminal pressure and dilatation to a decrease in pressure. This mechanism is important for the regulation of blood flow, capillary pressure and arterial pressure. The identity of the mechanosensory mechanism(s) for this response is incompletely understood but has been shown to include the integrins as cell-extracellular matrix receptors. The possibility that a cell-cell adhesion receptor is involved has not been studied. Thus, we tested the hypothesis that N-cadherin, a cell-cell adhesion molecule in vascular smooth muscle cells (VSMCs), was important for myogenic responsiveness. The purpose of this study was to investigate:1. whether cadherin inhibition blocks myogenic responses to increases in intraluminal pressure and 2. the effect of the cadherin or integrin blockade on pressure-induced changes in [Ca2+]i. Cadherin blockade was tested in isolated rat cremaster arterioles on myogenic
Looking for afferent glomerular arteriole? Find out information about afferent glomerular arteriole. An artery of small diameter that terminates in capillaries Explanation of afferent glomerular arteriole
The apparatus was transferred to an inverted microscope (Nikon TMS-F, 20× objective, Nikon, Melville, NY). Steady-state measurements of internal diameter at the midpoint of the segment were made using a high resolution CCD video camera (Hitachi KPC503, Hitachi, San Jose, CA) and a video caliper (Living Systems) calibrated using a stage micrometer. The vessel was superfused with PSS at a rate of 6 ml/min, and the chamber was maintained at 37°C. Chamber temperature and pH were monitored continuously using a probe (Oakton, series 35616, Singapore), and samples of the superfusing buffer were periodically drawn from the chamber for gas analysis (AVL Instruments, model 995, Graz, Austria). A plexiglas cover excluded ambient air from the chamber. The reservoir containing the perfusate and superfusate and the vessel chamber itself were bubbled with gas whose composition was adjusted, using separate tanks and regulators for each of oxygen, carbon dioxide, and nitrogen, to achieve Po2and Pco2values in ...
Previously, we found increased expression of l-arginine metabolizing enzymes in both kidneys from two-kidney, one-clip (2K1C) hypertensive rats (Helle F, Hultstrom M, Skogstrand T, Palm F, Iversen BM. Am J Physiol Renal Physiol 296: F78-F86, 2009). In the present study, we investigate whether AT(1) receptor activation can induce the changes observed in 2K1C. Four groups of rats were infused with 80 ng/min ANG II or saline for 14 days and/or given 60 mg x kg(-1) x day(-1) losartan. Gene expression was studied in isolated preglomerular vessels by RT-PCR. Dose-responses to ANG II were studied in isolated preglomerular vessels with and without acute NOS inhibition [10(-4) mol/l N(G)-nitro-l-arginine methyl ester (l-NAME)]. Expressions of endothelial nitric oxide synthase (eNOS), caveolin-1, and arginase-2 were not changed by ANG II infusion. CAT1 (0.3 8 +/- 0.07 to 0.73 +/- 0.12, P , 0.05), CAT2 (1.14 +/- 0.29 to 2.74 +/- 0.48), DDAH2 (1.09 +/- 0.27 to 2.3 +/- 0.46), and arginase-1 (1.08 +/- 0.17 to ...
Beginning in small radicals around the base of the alveoli, venules are formed through the coalescence of capillaries. These rapidly converge to a. point near the terminal arterioles about the intercalary duct to form venae terminales. The veins are short and there is but a single one accompanying each terminal arteriole. At the point of junction of several intercalary ducts, the accompanying terminal veins through their confluence form the intralobular veins which collect the blood from different portions of the lobule and terminate in the lobular vein. This vessel makes its exit from the lobule at the hilus, side by side with the lobular artery. There is no reduplication of the veins of the intralobular system. As soon as the veins leave the lobules, however, and enter the sublobular interspaces, the venous system is doubled, yielding venae comites to each successive division of the A. submaxillaris. The sublobular veins parallel the course of the artery, giving ofi numerous anastomotic ...
High blood pressure is the leading risk factor for death worldwide. One of the hallmarks is a rise of peripheral vascular resistance, which largely depends on arteriole tone. Ca2+-activated chloride currents (CaCCs) in vascular smooth muscle cells (VSMCs) are candidates for increasing vascular contractility. We analyzed the vascular tree and identified substantial CaCCs in VSMCs of the aorta and carotid arteries. CaCCs were small or absent in VSMCs of medium-sized vessels such as mesenteric arteries and larger retinal arterioles. In small vessels of the retina, brain, and skeletal muscle, where contractile intermediate cells or pericytes gradually replace VSMCs, CaCCs were particularly large. Targeted disruption of the calcium-activated chloride channel TMEM16A, also known as ANO1, in VSMCs, intermediate cells, and pericytes eliminated CaCCs in all vessels studied. Mice lacking vascular TMEM16A had lower systemic blood pressure and a decreased hypertensive response following vasoconstrictor ...
Nitroglycerin is, at typical doses, a VENOUS dilator. By decreasing venous return to the heart (preload) nitroglycerin decreases the filling pressure of the heart, decreasing myocardial wall tension, force of contraction, and by extension, myocardial workload and oxygen demand of the stressed tissue. Nitroglycerin only minor effect on arteries or arterioles at usual doses, although a high dose drip (greater than 40mcg/min) can have artery dilating effects. So, nitro does not dilate atherosclerotic arteries to allow blood to flow around any clots or occlusions in the arterial system of the heart. When nitroglycerin has been injected directly into a blocked coronary artery, it has not relieved pain! In other words, nitroglycerin eases coronary chest pain by reducing the hearts oxygen needs, NOT by providing more oxygen supply. Although blood pressure can drop with nitroglycerin, it can be minimized with the patient lying down ...
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Definition of capillary arteriole. Provided by Stedmans medical dictionary and Drugs.com. Includes medical terms and definitions.
Study finds that arterioles in the palms of fibromyalgia patients are overly dilated, which causes over-sensitization of the nerves, resulting in pa
Professor Layton is modeling renal function at the level of the nephron (the functional unit of the kidney) and at the level of nephron populations. In particular, he is studying tubuloglomerular feedback (TGF), the urine concentrating mechanism, and the hemodynamics of the afferent arteriole. Dynamic models for TGF and the afferent arteriole involve small systems of semilinear hyperbolic partial differential equations (PDEs) with time-delays, and coupled ODES, which are solved numerically for cases of physiological interest, or which are linearized for qualitative analytical investigation. Dynamic models for the concentrating mechanism involve large systems of coupled hyperbolic PDEs that describe tubular convection and epithelial transport. Numerical solutions of these PDEs help to integrate and interpret quantities determined by physiologists in many separate experiments.. ...
Professor Layton is modeling renal function at the level of the nephron (the functional unit of the kidney) and at the level of nephron populations. In particular, he is studying tubuloglomerular feedback (TGF), the urine concentrating mechanism, and the hemodynamics of the afferent arteriole. Dynamic models for TGF and the afferent arteriole involve small systems of semilinear hyperbolic partial differential equations (PDEs) with time-delays, and coupled ODES, which are solved numerically for cases of physiological interest, or which are linearized for qualitative analytical investigation. Dynamic models for the concentrating mechanism involve large systems of coupled hyperbolic PDEs that describe tubular convection and epithelial transport. Numerical solutions of these PDEs help to integrate and interpret quantities determined by physiologists in many separate experiments. ...
Endothelial cell, Ca2+-activated K channels (SKCa and IKCa channels) generate hyperpolarization that passes to the adjacent vascular smooth muscle cells to cause vasodilation in small resistance arterioles. IKCa channels expressed within endothelial cell projections toward the SMCs are activated by spontaneous Ca2+ events (Ca2+ puffs/pulsars). TRPV4 channels also cluster within this microdomain and are selectively activated at low intravascular pressure resulting in activation of endothelial cell IKCa channels and vasodilation, reducing the myogenic tone that underpins tissue blood-flow autoregulation. ...
Nebulized VasoconstrictorsEpinephrine stimulates alpha receptors and beta2 receptors. It constricts the precapillary arterioles, thus decreasing airway edema. Because of the potential adverse effects ... more
It is a mechanism that can be used to help control [[Blood pressure,blood pressure]]. Vasoconstriction of [[Arterioles,arterioles]] reduces their diameter. This reduction in lumen diameter causes the resistance to [[Blood,blood]] flow to increase as more of the [[Red blood cells,Red Blood Cells]] come into contact with the arteriole walls. This causes blood pressure to increase,ref,Dee Unglaub Silverthorn (2010) Human Physiology An Integrated Approach, Sixth Edition, Glenview: Pearson. Page 519,/ref ...
To tease apart the role of endothelial signaling in the living brain, they had to develop new ways to both image the brain at very high speeds, and also to selectively alter the ability of endothelial cells to propagate signals within intact vessels. The team achieved this through a range of techniques that use light and optics, including imaging using a high-speed camera with synchronized, strobed LED illumination to capture changes in the color, and thus the oxygenation level of flowing blood. Focused laser light was used in combination with a fluorescent dye within the bloodstream to cause oxidative damage to the inner endothelial layer of blood brain arterioles, while leaving the rest of the vessel intact and responsive. The team showed that, after damaging a small section of a vessel using their laser, the vessel no longer dilated beyond the damaged point. When the endothelium of a larger number of vessels was targeted in the same way, the overall blood flow response of the brain to ...
To tease apart the role of endothelial signaling in the living brain, they had to develop new ways to both image the brain at very high speeds, and also to selectively alter the ability of endothelial cells to propagate signals within intact vessels. The team achieved this through a range of techniques that use light and optics, including imaging using a high-speed camera with synchronized, strobed LED illumination to capture changes in the color, and thus the oxygenation level of flowing blood. Focused laser light was used in combination with a fluorescent dye within the bloodstream to cause oxidative damage to the inner endothelial layer of blood brain arterioles, while leaving the rest of the vessel intact and responsive. The team showed that, after damaging a small section of a vessel using their laser, the vessel no longer dilated beyond the damaged point. When the endothelium of a larger number of vessels was targeted in the same way, the overall blood flow response of the brain to ...
A dopamine D1 receptor agonist that is used as an antihypertensive agent. It lowers blood pressure through arteriolar vasodilation ...
Operation Sports presents the latest CHIKARA: Action Arcade Wrestling news, screenshots and videos. Looking for the CHIKARA: Action Arcade Wrestling release date or latest CHIKARA: Action Arcade Wrestling features? Youve come to the right place. ...
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Arcade Optical is your local optometrist in BROOKLINE serving all of your vision care needs. Call us today at (617) 232-9200 for an appointment.
Only a few years ago, console and arcade games were comparable graphically. In fact, it wasnt until the Dreamcast and the amazing Soul Calibur that console games began surpassing the quality offered in an arcade cabinet. Over the past couple of years, weve entered a gaming era where developers feel they must make use of every button on the controller and offer gameplay gimmicks to sell their products. Most Xbox games are the antithesis of the arcade classics, so seeing a good old fashioned shooter come to the box is a delight. However, the problem with porting arcade games to Xbox is that the graphics, sound, and depth rarely translate well. But if not for arcade ports, mindless shoot-em-ups -- where two buttons are all you need to survive -- wouldnt be available to hungry gamers who just want to stay on the couch and not go to the arcade.
Looney Labs is raising funds for PYRAMID ARCADE - 90 Pyramids, 22 Games, Endless Fun! on Kickstarter! Pyramid Arcade is a library of 22 games in one box, with 90 pyramids + boards, dice, & cards. From Looney Labs, creators of Fluxx.
Arteries carry the blood away from the heart and veins carry blood to the heart. Arteries are strong and thick as the oxygenated blood is being transported through them using a pumping action. They are also capable of expanding and contracting. The aorta is the main artery and this connects to the heart at the left ventricle, the aorta then divides into smaller arteries and even smaller arterioles as the blood is taken from the heart. When these arterioles reach their destination (ie: part of the body) they branch again into capillaries, these are thin walled and allow the fluids and gases to pass into and from the body tissues. These arterial capillaries then become venous capillaries. ...
This image from a thin (1µm) section shows sufficient detail to resolve secretory granules within juxtaglomerular cells, found in the wall of an afferent arteriole. (The clear white bubbles near the vascular endothelium and at upper right are preparation artefacts.). ...
Identify the molecular mechanism of pulmonary arteriole thrombosis in Sickle Cell Disease. FIVE KEYWORDS THAT DESCRIBE YOUR AREAS OF INTEREST ...
Grand Arcade of Mare Crisium by KECG Becka had never been strong, even before shed spent a year on a diet of potato-chips and heroin. But shed put on a bit of muscle in her new line of work and the wind always seemed to be at her back. The man she was after was…
Choose from 17 political characters and 4 stages as you battle your way through the Tree of Liberty. Reminiscent of the 1990s arcade fighting games, each pat...
The home features include: 60-foot swimming pool with waterfall, spa large enough for 20 people, retro arcade room, Star Trek movie theater Call-of-Duty room and more!
The Arcade Players will be treading the boards again at Long Eaton’s Duchess Theatre from February 11-14, with their latest production.
In Sidering Knockout, you goal is to knock all your opponents out cold and get the championship belt! Try to use combinations and dodge the opponents punches. A good tip would be to find the best key combination and use it all the time. Try not to get hit by spamming punches. Note: we are not responsible for any damage you may do to your keyboard! Show them whos boss in the ring. ...
OHMYGODDIDYOUSEETHAT?!? That bird. Right there. Yeah, thats the one. The one giving me the evil eye. You see it too? Right. Lets grab our drinks, sit…
The Typing of the DeadPlatform: Arcade game|Arcade, ported to Dreamcast and PC Genre: Deranged Release date: 1999/March, 2000 In the far too many years ...
As the Wii U is facing a dearth of system-selling titles at the moment, the fact that two of Capcoms most anticipated digital titles will not be available on the nascent platform is being seen as a genuine cause for concern, though it does explain why Capcom didnt announce the aforementioned titles for the console.. ...
If you experience the embarrassing situation of waking up with a wet and sticky spot at night then its the right time to stop night discharge. The condition…
Shock Troopers is a 1-2 player game where players select one of eight characters to play as. Each character has their own attack. Players also have to choose one of three routes to take. The object of the game is to go toward the end of the level and defeat the end-of-level boss, which is usually a ...
Le Tiny Arcade est un minuscule jeu darcade rétro imaginé par TinyCircuits et lancé sur Kickstarter. Ce studio, basé dans lOhio, a voulu reproduire le meuble du jeu darcade à petite échelle, avec un tout petit.... ...
Looking for online definition of afferent glomerular arteriole of kidney in the Medical Dictionary? afferent glomerular arteriole of kidney explanation free. What is afferent glomerular arteriole of kidney? Meaning of afferent glomerular arteriole of kidney medical term. What does afferent glomerular arteriole of kidney mean?
Objective Currently, there are no published data on retinal microvasculature size in human infants born at term. The purpose of this study was to determine the normal retinal microvasculature measurements in human infants born at term with normal birth weight and to compare these results with measurements in children and adults. Methods Retinal arteriole and venule measurements were obtained in a cohort of 20 full-term infants. Digital retinal images were obtained from both eyes after pupillary dilation using a digital retinal camera. Measurements of vessel diameter were then obtained using semi-automated software. Results Twenty infants (9 female infants and 11 male infants) were analyzed. The retinal arteriole diameter was 66.8-123.0 μm (mean, 85.5 (14.3) μm), and the venule diameter was 102.0-167.8 μm (mean, 130.0 (16.0) μm). There were no differences in the arterial or venule diameters between the male and female infants (83.2 (12.2) vs. 88.3 (16.9); P = 0.4372; 124.3 (16.0) vs. 137.0 (18.0); P
Looking for online definition of interlobular arteries in the Medical Dictionary? interlobular arteries explanation free. What is interlobular arteries? Meaning of interlobular arteries medical term. What does interlobular arteries mean?
The juxtaglomerular cells (JG cells, or granular cells) are cells in the kidney that synthesize, store, and secrete the enzyme renin. They are specialized smooth muscle cells mainly in the walls of the afferent arterioles, and some in the efferent arterioles, that deliver blood to the glomerulus. In synthesizing renin, they play a critical role in the renin-angiotensin system and thus in autoregulation of the kidney. Juxtaglomerular cells secrete renin in response to a drop in pressure detected by stretch receptors in the vascular walls, or when stimulated by macula densa cells. Macula densa cells are located in the distal convoluted tubule, and stimulate juxtaglomerular cells to release renin when they detect a drop in sodium concentration in tubular fluid. Together, juxtaglomerular cells, extraglomerular mesangial cells and macula densa cells comprise the juxtaglomerular apparatus. In appropriately stained tissue sections, juxtaglomerular cells are distinguished by their granulated cytoplasm. ...
Objective: To describe a new computer-assisted method to measure retinal vascular caliber over an extended area of the fundus. Methods: Retinal photographs taken from participants of the Singapore Malay Eye Study (n = 3280) were used for this study. Retinal vascular caliber was measured and summarized as central retinal artery equivalent (CRAE) and central retinal vein equivalent (CRVE) using a new semi-automated computer-based program. Measurements were made at the Standard zone (from 0.5 to 1.0 disk diameter) and an Extended zone (from 0.5 to 2.0 disk diameter). Results: Reliability of retinal vascular caliber measurement was high for the new Extended zone (intraclass correlation coefficients >0.90). Associations of CRAE with blood pressure were identical between the Extended and Standard zones (linear regression coefficient -2.53 vs. -2.61, z-test between the two measurements, p = 0.394). Associations of CRAE and CRVE with other cardiovascular risk factors were similar between measurements ...
C-peptide reduces diabetes-induced glomerular hyperfiltration in diabetic patients and experimental animal models. However, the mechanisms mediating the beneficial effect of C-peptide remain unclear. We investigated whether altered renal afferent-efferent arteriole tonus or alterations in tubular Na+ transport (T(Na)) in response to C-peptide administration mediate the reduction of diabetes-induced glomerular hyperfiltration. Glomerular filtration rate, filtration fraction, total and cortical renal blood flow, total kidney O2 consumption (QO2), T(Na), fractional Na+ and Li+ excretions, and tubular free-flow and stop-flow pressures were measured in anesthetized adult male normoglycemic and streptozotocin-diabetic Sprague-Dawley rats. The specific effect of C-peptide on transport-dependent QO2 was investigated in vitro in freshly isolated proximal tubular cells. C-peptide reduced glomerular filtration rate (-24%), stop-flow pressure (-8%), and filtration fraction (-17%) exclusively in diabetic ...
In this study, we demonstrate that (1) BM FRC-like cells are periarteriolar stromal cells that express PDPN in the BM, (2) PDPN binding to CLEC-2 positively regulates megakaryocyte expansion, and (3) CLEC-2/PDPN binding stimulates BM FRC-like cells to secrete CCL5 to promote PPF in megakaryocytes. The CLEC-2/PDPN axis between megakaryocytes and BM FRC-like cells constitutes a reciprocal interaction that generates the megakaryopoietic microenvironment at periarteriolar sites in the BM (supplemental Figure 7). These data support our hypothesis that BM FRC-like cells provide a CLEC-2/PDPN-dependent niche that potentiates megakaryocyte expansion and CCL5-mediated PPF.. In megakaryopoiesis, phosphatidylinositol 3-kinase/Akt signaling promotes the proliferation of megakaryocyte progenitors,36,37 and p44/42 signaling regulates megakaryocytic differentiation.38 Interestingly, p38 does not appear to be involved in megakaryopoietic processes.39 In this study, we found that PDPN binding to CLEC-2 increases ...
The microvessel density (MVD) was assessed in lymph nodes infiltrated by diffuse large B-cell lymphomas, mantle cell lymphomas, chronic lymphatic leukemia and follicular lymphomas, and in lymphadenitis. Serial sections of formalin-fixed and paraffin-embedded tissue were stained with antibodies against CD31, CD34 or Factor VIII. Using light microscopy and computerised image analysis, the number and size of individual immunostained vessel profiles within a preselected area size range corresponding to capillaries, postcapillary venules, small collecting venules and small arterioles were determined. A significantly larger number of vessels were registered following staining with anti-CD34 than with anti-CD31 or anti-Factor VIII. Moreover, among the smallest capillary-sized vessel profiles in all lesion types, there was a selective relative loss of stainability of anti-CD31 and anti-Factor VIII, resulting in a substantial total loss of visualised capillary-sized vessels compared with anti-CD34. In ...

Functional Microvascular Anatomy of the Horse Eye: A Scanning Electron Microscopic Study of Corrosion CastsFunctional Microvascular Anatomy of the Horse Eye: A Scanning Electron Microscopic Study of Corrosion Casts

The retinal arterioles and venules ran in closely related pairs, and the capillaries formed hairpin loops. No central retinal ... The retinal arterioles and venules ran in closely related pairs, and the capillaries formed hairpin loops. No central retinal ...
more infohttp://www.scirp.org/journal/PaperInformation.aspx?paperID=46064

Confocal Microscopy of Corrosion CastsConfocal Microscopy of Corrosion Casts

uncorroded glomerulus and arteriole. uncorroded glomeruli and kidney tubules. uncorroded fish gill capillaries ...
more infohttp://www1.udel.edu/biology/Wags/histopage/vascularmodelingpage/confocal/confocalmicroscopy.html

Publications | Department of Vet. Anatomy And PhysiologyPublications | Department of Vet. Anatomy And Physiology

... that formed arterioles (A3). The arterioles formed capillaries that participated in the formation of the parabronchial mantle. ...
more infohttp://vetanatomy.uonbi.ac.ke/uon_publications/author/1489

Control of ArteriolesControl of Arterioles

... Arterioles are the smallests vessels of the arterial system, with a diameter of about 1/3 millimeter or ... OTHER ARTERIOLES: Most of the arterioles in the body are affected to at least some extent by local chemical factors that adjust ... This is determined by the lumped effects of all the arterioles in the body and is termed the total peripheral resistance. ... The arterioles are absolutely a key effector organ in the control of mean arterial pressure. Recall our model for the arterial ...
more infohttp://courses.washington.edu/conj/heart/arterioles2011.htm

Heart-and-Stroke-Encyclopedia - arteriolesHeart-and-Stroke-Encyclopedia - arterioles

arterioles Arterioles are small, muscular branches of arteries. When they contract, they increase resistance to blood flow, and ...
more infohttp://www.heart.org/HEARTORG/Encyclopedia/Heart-and-Stroke-Encyclopedia_UCM_445084_Encyclopedia.jsp?levelSelected=1&title=arterioles

Heart-and-Stroke-Encyclopedia - arteriolesHeart-and-Stroke-Encyclopedia - arterioles

arterioles Arterioles are small, muscular branches of arteries. When they contract, they increase resistance to blood flow, and ...
more infohttp://www.heart.org/HEARTORG/Encyclopedia/Heart-and-Stroke-Encyclopedia_UCM_445084_ContentIndex.jsp?levelSelected=1&title=arterioles

Afferent arteriole | blood vessel | Britannica.comAfferent arteriole | blood vessel | Britannica.com

Arteries and arterioles: …off short branches called the afferent arterioles, which carry blood to the glomeruli where they ... Other articles where Afferent arteriole is discussed: renal system: ... In renal system: Arteries and arterioles. …off short branches called the afferent arterioles, which carry blood to the ... of plasma so that the afferent arterioles skim off more plasma than cells. If the arteriolar blood pressure rises, the skimming ...
more infohttps://www.britannica.com/science/afferent-arteriole

Capillary arteriole definition | Drugs.comCapillary arteriole definition | Drugs.com

Definition of capillary arteriole. Provided by Stedmans medical dictionary and Drugs.com. Includes medical terms and ...
more infohttps://www.drugs.com/dict/capillary-arteriole.html

Efferent Arteriole - Kidney Blood FilteringEfferent Arteriole - Kidney Blood Filtering

Efferent Arteriole. The efferent arteriole carries blood away from the glomerulus. Because it has a smaller diameter than the ... afferent arteriole, it creates some resistance to blood flow, producing the back-up of blood in the glomerulus which creates ...
more infohttp://www.innerbody.com/image_card08/card80-new.html

Superoxide Modulates Myogenic Contractions of Mouse Afferent Arterioles | HypertensionSuperoxide Modulates Myogenic Contractions of Mouse Afferent Arterioles | Hypertension

Afferent arterioles were perfused at 60 mm Hg to provide some basal tone and incubated with graded concentration of H2O2 for 15 ... TP receptor-mediated vasoconstriction in microperfused afferent arterioles: role O2- and NO. Am J Physiol. 2000;48:F302-F308. ... Superoxide Modulates Myogenic Contractions of Mouse Afferent Arterioles. En Yin Lai, Anton Wellstein, William J. Welch, ... Angiotensin II, reactive oxygen species, and Ca2+ signaling in afferent arterioles. Am J Physiol Renal Physiol. 2005;289:F1012- ...
more infohttp://hyper.ahajournals.org/content/58/4/650

Arteriole Synonyms, Arteriole Antonyms | Thesaurus.comArteriole Synonyms, Arteriole Antonyms | Thesaurus.com

Synonyms for arteriole at Thesaurus.com with free online thesaurus, antonyms, and definitions. Find descriptive alternatives ... RELATED WORDS AND SYNONYMS FOR ARTERIOLE. blood vessel. nounblood flow pathway ...
more infohttps://www.thesaurus.com/browse/arteriole

Precapillary arteriole - definition of precapillary arteriole by The Free DictionaryPrecapillary arteriole - definition of precapillary arteriole by The Free Dictionary

precapillary arteriole synonyms, precapillary arteriole pronunciation, precapillary arteriole translation, English dictionary ... definition of precapillary arteriole. n. One of the small terminal branches of an artery, especially one that connects with a ... arteriole. (redirected from precapillary arteriole). Also found in: Thesaurus, Medical, Encyclopedia.. Related to precapillary ... arteriole. (ɑːˈtɪərɪˌəʊl) n. (Anatomy) anatomy any of the small subdivisions of an artery that form thin-walled vessels ending ...
more infohttp://www.thefreedictionary.com/precapillary+arteriole

CONCERNING THE GEOMETRIC SHAPES OF ARTERIES AND ARTERIOLESCONCERNING THE GEOMETRIC SHAPES OF ARTERIES AND ARTERIOLES

1. Measurements of the internal diameters and lengths of branchless segments of mesenteric arterioles of frogs and mice show ... Saunders and Knisely (63) found that the maximal internal diameters to which the terminal mesenteric arterioles can distend as ... Saunders and Knisely (63) found unagglutinated blood flowing at physiologic rates through terminal arterioles as narrow as, ...
more infohttp://connection.ebscohost.com/c/articles/16357939/concerning-geometric-shapes-arteries-arterioles

Arterioles of the Lenticular Nucleus in CADASIL | StrokeArterioles of the Lenticular Nucleus in CADASIL | Stroke

Arterioles of the Lenticular Nucleus in CADASIL. Qing Miao, Timo Paloneva, Seppo Tuisku, Susanna Roine, Minna Poyhonen, Matti ... Arterioles of the Lenticular Nucleus in CADASIL. Qing Miao, Timo Paloneva, Seppo Tuisku, Susanna Roine, Minna Poyhonen, Matti ... Arterioles of the Lenticular Nucleus in CADASIL. Qing Miao, Timo Paloneva, Seppo Tuisku, Susanna Roine, Minna Poyhonen, Matti ...
more infohttp://stroke.ahajournals.org/content/early/2006/07/27/01.STR.0000236838.84150.c2

Arteriole - Biology-Online DictionaryArteriole - Biology-Online Dictionary

Arteriole (Science: anatomy) a minute artery, especially one that leads to a capillary. One of the small thin-walled arteries ... These arterioles get progressively smaller the more distanced they are from the heart, as most of the blood supply is required ... that end in capillaries.Arterioles are responsible for carrying oxygenated blood from the heart to all over the body. ... Retrieved from "https://www.biology-online.org/dictionary/index.php?title=Arteriole&oldid=83013" ...
more infohttps://www.biology-online.org/dictionary/Arteriole

Nox2 Deficiency Prevents Hypertension-Induced Vascular Dysfunction and Hypertrophy in Cerebral ArteriolesNox2 Deficiency Prevents Hypertension-Induced Vascular Dysfunction and Hypertrophy in Cerebral Arterioles

G. L. Baumbach, C. D. Sigmund, T. Bottiglieri, and S. R. Lentz, "Structure of cerebral arterioles in cystathionine β-synthase- ... G. L. Baumbach, C. D. Sigmund, and F. M. Faraci, "Structure of cerebral arterioles in mice deficient in expression of the gene ... G. L. Baumbach, S. P. Didion, and F. M. Faraci, "Hypertrophy of cerebral arterioles in mice deficient in expression of the gene ... G. L. Baumbach, P. B. Dobrin, M. N. Hart, and D. D. Heistad, "Mechanics of cerebral arterioles in hypertensive rats," ...
more infohttps://www.hindawi.com/journals/ijhy/2013/793630/ref/

Overview of Arterioles in Blood PressureOverview of Arterioles in Blood Pressure

Learn about Arterioles, the most highly regulated blood vessels in the body that contribute the most to the rise and fall in ... Arteriole Disorders When the body is functioning as it should, the arterioles help ensure that the blood pressure remains ... Arterioles share many of the properties of arteries. Theyre strong, have relatively thick walls, and contain a high percentage ... The specialized blood vessels known as arterioles may be small in stature, but they play a big role in heart health. As you ...
more infohttps://www.verywellhealth.com/part-3-arterioles-1763960

Afferent arterioles - WikipediaAfferent arterioles - Wikipedia

The afferent arterioles branch from the renal artery, which supplies blood to the kidneys. The afferent arterioles later ... The afferent arterioles are a group of blood vessels that supply the nephrons in many excretory systems. They play an important ... If the afferent arterioles are constricted then the blood pressure in the capillaries of the kidneys will drop. Efferent ... The macula densa cell can also increase the blood pressure of the afferent arterioles by decreasing the synthesis of adenosine ...
more infohttps://en.wikipedia.org/wiki/Afferent_arterioles

Constriction of Pial Arterioles Produced by Prostaglandin F2α | StrokeConstriction of Pial Arterioles Produced by Prostaglandin F2α | Stroke

Constriction of Pial Arterioles Produced by Prostaglandin F2α. WILLIAM I. ROSENBLUM ... Prostaglandin F2α constricted pial arterioles when locally applied to the cerebral surface. Norepinephrine and serotonin each ...
more infohttp://stroke.ahajournals.org/content/6/3/293

Capillary arteriole | definition of capillary arteriole by Medical dictionaryCapillary arteriole | definition of capillary arteriole by Medical dictionary

What is capillary arteriole? Meaning of capillary arteriole medical term. What does capillary arteriole mean? ... Looking for online definition of capillary arteriole in the Medical Dictionary? capillary arteriole explanation free. ... capillary arteriole. cap·il·lar·y ar·te·ri·ole. a minute artery that terminates in a capillary. ... Capillary arteriole , definition of capillary arteriole by Medical dictionary https://medical-dictionary.thefreedictionary.com/ ...
more infohttps://medical-dictionary.thefreedictionary.com/capillary+arteriole

Cyclooxygenase inhibition improves endothelial vasomotor dysfunction of visceral adipose arterioles in human obesity.  - PubMed...Cyclooxygenase inhibition improves endothelial vasomotor dysfunction of visceral adipose arterioles in human obesity. - PubMed...

Treatment of visceral arterioles with L-NAME (light gray, triangle symbol) completely abolished indomethacin-induced ... Arterioles from visceral fat exhibited impaired endothelium-dependent, acetylcholine-mediated vasodilation, compared to the ... Cyclooxygenase inhibition improves endothelial vasomotor dysfunction of visceral adipose arterioles in human obesity.. Farb MG1 ... Vasomotor function was assessed in response to endothelium-dependent agonists using videomicroscopy of small arterioles from ...
more infohttps://www.ncbi.nlm.nih.gov/pubmed/23640904

Molecular Vision: Vasodilatory mechanisms of unoprostone isopropyl in isolated porcine retinal arteriolesMolecular Vision: Vasodilatory mechanisms of unoprostone isopropyl in isolated porcine retinal arterioles

reported that, in the retinal arterioles, UI caused vasodilation only in endothelin-1 (ET-1)-pre-contracted arterioles but did ... Previous studies have reported the involvement of various K channels in the vasodilation of the retinal arterioles [9,10,12,18, ... Dilation of retinal arterioles induced by UI. The basal tone in all vessels (n=38) ranged from 53% to 78% (average, ~59% ± 4%) ... Cannulated, pressurized arterioles were bathed in physiologic salt solution (PSS) with albumin (0.1%) at 36 to 37 °C to allow ...
more infohttp://www.molvis.org/molvis/v21/699/

Arteriole, TEM - Stock Image C011/9459 - Science Photo LibraryArteriole, TEM - Stock Image C011/9459 - Science Photo Library

Coloured transmission electron micrograph (TEM) of a section through the wall of an arteriole, showing smooth muscle (brown), ... Caption: Arteriole. Coloured transmission electron micrograph (TEM) of a section through the wall of an arteriole, showing ... Keywords: anatomical, anatomy, arteriole, basal lamina, basement lamina, basement membrane, biological, biology, blood vessel, ...
more infohttp://www.sciencephoto.com/media/442820/view

Postischemic Reperfusion Causes Smooth Muscle Calcium Sensitization and Vasoconstriction of Parenchymal Arterioles.Postischemic Reperfusion Causes Smooth Muscle Calcium Sensitization and Vasoconstriction of Parenchymal Arterioles.

Parenchymal arterioles (PAs) are high-resistance vessels in the brain that connect pial vessels to the microcirculation. We ... BACKGROUND AND PURPOSE: Parenchymal arterioles (PAs) are high-resistance vessels in the brain that connect pial vessels to the ... Sensitivity of the contractile apparatus to calcium was measured in permeabilized arterioles using Staphylococcus aureus α- ...
more infohttp://www.biomedsearch.com/nih/Postischemic-Reperfusion-Causes-Smooth-Muscle/24968928.html

Straight arterioles of kidney - WikipediaStraight arterioles of kidney - Wikipedia

Each straight arteriole has a hairpin turn in the medulla and carries blood at a very slow rate - two factors crucial in the ... The straight arterioles are peritubular capillaries, specifically those that surround the loop of Henle. On a histological ... On the descending portion of the straight arterioles, NaCl and urea are reabsorbed into the blood, while water is secreted. On ... For the intestinal structure, see Vasa recta (intestines) In the blood supply of the kidney, the straight arterioles of kidney ...
more infohttps://en.wikipedia.org/wiki/Straight_arterioles_of_kidney
  • Each straight arteriole has a hairpin turn in the medulla and carries blood at a very slow rate - two factors crucial in the maintenance of countercurrent exchange that prevent washout of the concentration gradients established in the renal medulla. (wikipedia.org)
  • 2 Renal autoregulation depends primarily on a rapid myogenic contraction of the afferent arteriole 3 followed by a tubuloglomerular feedback response. (ahajournals.org)
  • The mouse isolated perfused renal afferent arteriole displayed a linear increase in active wall tension above a PP of ≈40 mm Hg, which defined the myogenic response. (ahajournals.org)
  • Drugs, such as the immunosuppressants cyclosporine and tacrolimus, chemo-therapeutic drugs bleomycin and cisplatin, clopidogrel, oestrogen-containing oral contraceptives and quinine may cause thrombosis in the afferent renal arteriole and glomerulus. (thefreedictionary.com)
  • Results indicate that in isolated renal arterioles AP III dilates preconstricted AA but constricts EA that have either not been pretreated or have been preconstricted with other agonists. (physiology.org)
  • We have recently documented the constitutive expression of arginase-I in porcine coronary arterioles and demonstrated its functional role in modulating coronary microvascular tone under physiological 12 and pathophysiological conditions. (ahajournals.org)
  • Raynaud's phenomenon is an abnormal vasospasm of digital arteries, precapillary arterioles , and dermal arteriovenous shunts that occurs in response to cold and various other stimuli. (thefreedictionary.com)
  • They discovered that people with FM had more vasodilation in the tiny little arterioles (smaller than arteries) that connect to the tiny little venules (smaller than veins) that connect to each other through shunts. (prohealth.com)
  • Excessive Peptidergic Sensory Innervation of Cutaneous Arteriole-Venule Shunts (AVS) in the Palmar Glabrous Skin of Fibromyalgia Patients: Implications for Widespread Deep Tissue Pain and Fatigue. (prohealth.com)
  • To determine if peripheral neuropathology exists among the innervation of cutaneous arterioles and arteriole-venule shunts (AVS) in fibromyalgia (FM) patients. (prohealth.com)
  • Saunders and Knisely (63) found unagglutinated blood flowing at physiologic rates through terminal arterioles as narrow as, depending upon species, from 5 to 7.7 micra in diameter. (ebscohost.com)
  • In a typical arteriole with an average diameter of ~35 μm, oscillatory vasomotion of a 5-6 μm magnitude was accompanied by nearly uniform [Ca 2+ ] oscillations from ~0.1 to 0.5 μM, with maximum [Ca 2+ ] occurring immediately before the rapid decrease in diameter. (frontiersin.org)
  • Coloured transmission electron micrograph (TEM) of a section through the wall of an arteriole, showing smooth muscle (brown), endothelial cells (green), and an inner and outer lamina (membrane, blue). (sciencephoto.com)
  • Mitochondrial uncoupling agents could potentially reverse endothelial dysfunction due to HG in intact human arterioles. (ahajournals.org)
  • Effect of intermittent normoxia on muscularization of pulmonary arterioles induced by chronic hypoxia in rats. (nih.gov)
  • Unlike many structures, arterioles do not have the dual innervation by both sympathetic and parasympathetic nerves. (washington.edu)
  • Cutaneous arterioles and AVS receive a convergence of vasoconstrictive sympathetic innervation, and vasodilatory small-fiber sensory innervation. (prohealth.com)
  • In contrast, sensory and sympathetic innervation to arterioles remained normal. (prohealth.com)
  • Oscillatory vasomotion or irregular contractions were observed in most arterioles (71%), with the greatest oscillatory frequency observed at 0.25 s −1 . (frontiersin.org)
  • 1. Measurements of the internal diameters and lengths of branchless segments of mesenteric arterioles of frogs and mice show those geometrically to be cone-shaped, not cylindrical. (ebscohost.com)
  • Two-photon fluorescence microscopy and conscious, restrained optical biosensor mice were used to study smooth muscle Ca 2+ signaling in ear arterioles. (frontiersin.org)
  • In contrast, vasomotion and dynamic Ca 2+ signals were rarely observed in ear arterioles of anesthetized exMLCK biosensor mice. (frontiersin.org)
  • FRET-based biosensor mice and two-photon imaging provided the first measurements of [Ca 2+ ] in vascular smooth muscle cells in arterioles of conscious animals. (frontiersin.org)
  • Here we report the first non-invasive measurements of intracellular smooth muscle [Ca 2+ ] in conscious mouse arterioles. (frontiersin.org)
  • These arterioles get progressively smaller the more distanced they are from the heart , as most of the blood supply is required by the major organs positioned close to the heart and is provided by the [[arteries. (biology-online.org)