Natriuresis: Sodium excretion by URINATION.Diuresis: An increase in the excretion of URINE. (McGraw-Hill Dictionary of Scientific and Technical Terms, 6th ed)Sodium: A member of the alkali group of metals. It has the atomic symbol Na, atomic number 11, and atomic weight 23.Kidney: Body organ that filters blood for the secretion of URINE and that regulates ion concentrations.Atrial Natriuretic Factor: A potent natriuretic and vasodilatory peptide or mixture of different-sized low molecular weight PEPTIDES derived from a common precursor and secreted mainly by the HEART ATRIUM. All these peptides share a sequence of about 20 AMINO ACIDS.Renal Circulation: The circulation of the BLOOD through the vessels of the KIDNEY.Natriuretic Agents: Endogenous or exogenous chemicals that regulate the WATER-ELECTROLYTE BALANCE in the body. They consist of peptides and non-peptide compounds.Glomerular Filtration Rate: The volume of water filtered out of plasma through glomerular capillary walls into Bowman's capsules per unit of time. It is considered to be equivalent to INULIN clearance.Blood Pressure: PRESSURE of the BLOOD on the ARTERIES and other BLOOD VESSELS.Furosemide: A benzoic-sulfonamide-furan. It is a diuretic with fast onset and short duration that is used for EDEMA and chronic RENAL INSUFFICIENCY.Water-Electrolyte Balance: The balance of fluid in the BODY FLUID COMPARTMENTS; total BODY WATER; BLOOD VOLUME; EXTRACELLULAR SPACE; INTRACELLULAR SPACE, maintained by processes in the body that regulate the intake and excretion of WATER and ELECTROLYTES, particularly SODIUM and POTASSIUM.Aldosterone: A hormone secreted by the ADRENAL CORTEX that regulates electrolyte and water balance by increasing the renal retention of sodium and the excretion of potassium.Aminohippuric Acids: A group of glycine amides of aminobenzoic acids.Diuretics: Agents that promote the excretion of urine through their effects on kidney function.Inulin: A starch found in the tubers and roots of many plants. Since it is hydrolyzable to FRUCTOSE, it is classified as a fructosan. It has been used in physiologic investigation for determination of the rate of glomerular function.Kidney Tubules: Long convoluted tubules in the nephrons. They collect filtrate from blood passing through the KIDNEY GLOMERULUS and process this filtrate into URINE. Each renal tubule consists of a BOWMAN CAPSULE; PROXIMAL KIDNEY TUBULE; LOOP OF HENLE; DISTAL KIDNEY TUBULE; and KIDNEY COLLECTING DUCT leading to the central cavity of the kidney (KIDNEY PELVIS) that connects to the URETER.Renin: A highly specific (Leu-Leu) endopeptidase that generates ANGIOTENSIN I from its precursor ANGIOTENSINOGEN, leading to a cascade of reactions which elevate BLOOD PRESSURE and increase sodium retention by the kidney in the RENIN-ANGIOTENSIN SYSTEM. The enzyme was formerly listed as EC Medulla: The internal portion of the kidney, consisting of striated conical masses, the renal pyramids, whose bases are adjacent to the cortex and whose apices form prominent papillae projecting into the lumen of the minor calyces.Angiotensin II Type 2 Receptor Blockers: Agents that antagonize the ANGIOTENSIN II TYPE 2 RECEPTOR.Sodium, Dietary: Sodium or sodium compounds used in foods or as a food. The most frequently used compounds are sodium chloride or sodium glutamate.Angiotensin III: A heptapeptide formed from ANGIOTENSIN II after the removal of an amino acid at the N-terminal by AMINOPEPTIDASE A. Angiotensin III has the same efficacy as ANGIOTENSIN II in promoting ALDOSTERONE secretion and modifying renal blood flow, but less vasopressor activity (about 40%).Electrolytes: Substances that dissociate into two or more ions, to some extent, in water. Solutions of electrolytes thus conduct an electric current and can be decomposed by it (ELECTROLYSIS). (Grant & Hackh's Chemical Dictionary, 5th ed)Bendroflumethiazide: A thiazide diuretic with actions and uses similar to those of HYDROCHLOROTHIAZIDE. It has been used in the treatment of familial hyperkalemia, hypertension, edema, and urinary tract disorders. (From Martindale, The Extra Pharmacopoeia, 30th ed, p810)Kidney Tubules, Proximal: The renal tubule portion that extends from the BOWMAN CAPSULE in the KIDNEY CORTEX into the KIDNEY MEDULLA. The proximal tubule consists of a convoluted proximal segment in the cortex, and a distal straight segment descending into the medulla where it forms the U-shaped LOOP OF HENLE.Blood Volume: Volume of circulating BLOOD. It is the sum of the PLASMA VOLUME and ERYTHROCYTE VOLUME.Bufanolides: Cyclopentanophenanthrenes with a 6-membered lactone ring attached at the 17-position and SUGARS attached at the 3-position. They are found in BUFONIDAE and often possess cardiotonic properties.Sodium Chloride: A ubiquitous sodium salt that is commonly used to season food.Potassium: An element in the alkali group of metals with an atomic symbol K, atomic number 19, and atomic weight 39.10. It is the chief cation in the intracellular fluid of muscle and other cells. Potassium ion is a strong electrolyte that plays a significant role in the regulation of fluid volume and maintenance of the WATER-ELECTROLYTE BALANCE.Sodium Chloride, Dietary: Sodium chloride used in foods.Urination: Discharge of URINE, liquid waste processed by the KIDNEY, from the body.Denervation: The resection or removal of the nerve to an organ or part. (Dorland, 28th ed)Hypertension: Persistently high systemic arterial BLOOD PRESSURE. Based on multiple readings (BLOOD PRESSURE DETERMINATION), hypertension is currently defined as when SYSTOLIC PRESSURE is consistently greater than 140 mm Hg or when DIASTOLIC PRESSURE is consistently 90 mm Hg or more.Vasopressins: Antidiuretic hormones released by the NEUROHYPOPHYSIS of all vertebrates (structure varies with species) to regulate water balance and OSMOLARITY. In general, vasopressin is a nonapeptide consisting of a six-amino-acid ring with a cysteine 1 to cysteine 6 disulfide bridge or an octapeptide containing a CYSTINE. All mammals have arginine vasopressin except the pig with a lysine at position 8. Vasopressin, a vasoconstrictor, acts on the KIDNEY COLLECTING DUCTS to increase water reabsorption, increase blood volume and blood pressure.Urine: Liquid by-product of excretion produced in the kidneys, temporarily stored in the bladder until discharge through the URETHRA.Fenoldopam: A dopamine D1 receptor agonist that is used as an antihypertensive agent. It lowers blood pressure through arteriolar vasodilation.Arginine Vasopressin: The predominant form of mammalian antidiuretic hormone. It is a nonapeptide containing an ARGININE at residue 8 and two disulfide-linked cysteines at residues of 1 and 6. Arg-vasopressin is used to treat DIABETES INSIPIDUS or to improve vasomotor tone and BLOOD PRESSURE.Receptor, Angiotensin, Type 2: An angiotensin receptor subtype that is expressed at high levels in fetal tissues. Many effects of the angiotensin type 2 receptor such as VASODILATION and sodium loss are the opposite of that of the ANGIOTENSIN TYPE 1 RECEPTOR.Dogs: The domestic dog, Canis familiaris, comprising about 400 breeds, of the carnivore family CANIDAE. They are worldwide in distribution and live in association with people. (Walker's Mammals of the World, 5th ed, p1065)Sodium Chloride Symporters: A subclass of symporters found in KIDNEY TUBULES, DISTAL that are the major pathway for salt resorption. Inhibition of these symporters by BENZOTHIADIAZINES is the basis of action of some DIURETICS.Isotonic Solutions: Solutions having the same osmotic pressure as blood serum, or another solution with which they are compared. (From Grant & Hackh's Chemical Dictionary, 5th ed & Dorland, 28th ed)Cyclic GMP: Guanosine cyclic 3',5'-(hydrogen phosphate). A guanine nucleotide containing one phosphate group which is esterified to the sugar moiety in both the 3'- and 5'-positions. It is a cellular regulatory agent and has been described as a second messenger. Its levels increase in response to a variety of hormones, including acetylcholine, insulin, and oxytocin and it has been found to activate specific protein kinases. (From Merck Index, 11th ed)Renin-Angiotensin System: A BLOOD PRESSURE regulating system of interacting components that include RENIN; ANGIOTENSINOGEN; ANGIOTENSIN CONVERTING ENZYME; ANGIOTENSIN I; ANGIOTENSIN II; and angiotensinase. Renin, an enzyme produced in the kidney, acts on angiotensinogen, an alpha-2 globulin produced by the liver, forming ANGIOTENSIN I. Angiotensin-converting enzyme, contained in the lung, acts on angiotensin I in the plasma converting it to ANGIOTENSIN II, an extremely powerful vasoconstrictor. Angiotensin II causes contraction of the arteriolar and renal VASCULAR SMOOTH MUSCLE, leading to retention of salt and water in the KIDNEY and increased arterial blood pressure. In addition, angiotensin II stimulates the release of ALDOSTERONE from the ADRENAL CORTEX, which in turn also increases salt and water retention in the kidney. Angiotensin-converting enzyme also breaks down BRADYKININ, a powerful vasodilator and component of the KALLIKREIN-KININ SYSTEM.Osmolar Concentration: The concentration of osmotically active particles in solution expressed in terms of osmoles of solute per liter of solution. Osmolality is expressed in terms of osmoles of solute per kilogram of solvent.Fludrocortisone: A synthetic mineralocorticoid with anti-inflammatory activity.Urodynamics: The mechanical laws of fluid dynamics as they apply to urine transport.Saline Solution, Hypertonic: Hypertonic sodium chloride solution. A solution having an osmotic pressure greater than that of physiologic salt solution (0.9 g NaCl in 100 ml purified water).Hyponatremia: Deficiency of sodium in the blood; salt depletion. (Dorland, 27th ed)Solute Carrier Family 12, Member 1: Na-K-Cl transporter in the ASCENDING LIMB OF LOOP OF HENLE. It mediates active reabsorption of sodium chloride and is inhibited by LOOP DIURETICS such as FUROSEMIDE; and BUMETANIDE. Mutations in the gene encoding SLC12A1 are associated with a BARTTER SYNDROME.Kallikrein-Kinin System: A system of metabolic interactions by products produced in the distal nephron of the KIDNEY. These products include KALLIKREIN; KININS; KININASE I; KININASE II; and ENKEPHALINASE. This system participates in the control of renal functions. It interacts with the RENIN-ANGIOTENSIN-ALDOSTERONE SYSTEM to regulate BLOOD PRESSURE, generation of PROSTAGLANDINS, release of VASOPRESSINS, and WATER-ELECTROLYTE BALANCE.Kidney Tubules, Distal: The portion of renal tubule that begins from the enlarged segment of the ascending limb of the LOOP OF HENLE. It reenters the KIDNEY CORTEX and forms the convoluted segments of the distal tubule.Nephrons: The functional units of the kidney, consisting of the glomerulus and the attached tubule.Hemodynamics: The movement and the forces involved in the movement of the blood through the CARDIOVASCULAR SYSTEM.Natriuretic Peptides: Peptides that regulate the WATER-ELECTROLYTE BALANCE in the body, also known as natriuretic peptide hormones. Several have been sequenced (ATRIAL NATRIURETIC FACTOR; BRAIN NATRIURETIC PEPTIDE; C-TYPE NATRIURETIC PEPTIDE).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.Dehydration: The condition that results from excessive loss of water from a living organism.Receptors, Atrial Natriuretic Factor: Cell surface proteins that bind ATRIAL NATRIURETIC FACTOR with high affinity and trigger intracellular changes influencing the behavior of cells. They contain intrinsic guanylyl cyclase activity.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.Kidney Cortex: The outer zone of the KIDNEY, beneath the capsule, consisting of KIDNEY GLOMERULUS; KIDNEY TUBULES, DISTAL; and KIDNEY TUBULES, PROXIMAL.Kidney Function Tests: Laboratory tests used to evaluate how well the kidneys are working through examination of blood and urine.Lithium: An element in the alkali metals family. It has the atomic symbol Li, atomic number 3, and atomic weight [6.938; 6.997]. Salts of lithium are used in treating BIPOLAR DISORDER.Diet, Sodium-Restricted: A diet which contains very little sodium chloride. It is prescribed by some for hypertension and for edematous states. (Dorland, 27th ed)Hydrostatic Pressure: The pressure due to the weight of fluid.Water Deprivation: The withholding of water in a structured experimental situation.Sodium Chloride Symporter Inhibitors: Agents that inhibit SODIUM CHLORIDE SYMPORTERS. They act as DIURETICS. Excess use is associated with HYPOKALEMIA.Parabiosis: The experimental joining of two individuals for the purpose of studying the effects of one on the other.Renal Agents: Drugs used for their effects on the kidneys' regulation of body fluid composition and volume. The most commonly used are the diuretics. Also included are drugs used for their antidiuretic and uricosuric actions, for their effects on the kidneys' clearance of other drugs, and for diagnosis of renal function.Meclofenamic Acid: A non-steroidal anti-inflammatory agent with antipyretic and antigranulation activities. It also inhibits prostaglandin biosynthesis.Punctures: Incision of tissues for injection of medication or for other diagnostic or therapeutic procedures. Punctures of the skin, for example may be used for diagnostic drainage; of blood vessels for diagnostic imaging procedures.Thiorphan: A potent inhibitor of membrane metalloendopeptidase (ENKEPHALINASE). Thiorphan potentiates morphine-induced ANALGESIA and attenuates naloxone-precipitated withdrawal symptoms.Polyuria: Urination of a large volume of urine with an increase in urinary frequency, commonly seen in diabetes (DIABETES MELLITUS; DIABETES INSIPIDUS).Plasma Substitutes: Any liquid used to replace blood plasma, usually a saline solution, often with serum albumins, dextrans or other preparations. These substances do not enhance the oxygen- carrying capacity of blood, but merely replace the volume. They are also used to treat dehydration.Hypertension, Renal: Persistent high BLOOD PRESSURE due to KIDNEY DISEASES, such as those involving the renal parenchyma, the renal vasculature, or tumors that secrete RENIN.Melanocyte-Stimulating Hormones: Peptides with the ability to stimulate pigmented cells MELANOCYTES in mammals and MELANOPHORES in lower vertebrates. By stimulating the synthesis and distribution of MELANIN in these pigmented cells, they increase coloration of skin and other tissue. MSHs, derived from pro-opiomelanocortin (POMC), are produced by MELANOTROPHS in the INTERMEDIATE LOBE OF PITUITARY; CORTICOTROPHS in the ANTERIOR LOBE OF PITUITARY, and the hypothalamic neurons in the ARCUATE NUCLEUS OF HYPOTHALAMUS.Water-Electrolyte Imbalance: Disturbances in the body's WATER-ELECTROLYTE BALANCE.Sodium-Potassium-Exchanging ATPase: An enzyme that catalyzes the active transport system of sodium and potassium ions across the cell wall. Sodium and potassium ions are closely coupled with membrane ATPase which undergoes phosphorylation and dephosphorylation, thereby providing energy for transport of these ions against concentration gradients.Renal Artery: A branch of the abdominal aorta which supplies the kidneys, adrenal glands and ureters.Anesthesia: A state characterized by loss of feeling or sensation. This depression of nerve function is usually the result of pharmacologic action and is induced to allow performance of surgery or other painful procedures.Chlorothiazide: A thiazide diuretic with actions and uses similar to those of HYDROCHLOROTHIAZIDE. (From Martindale, The Extra Pharmacopoeia, 30th ed, p812)Neprilysin: Enzyme that is a major constituent of kidney brush-border membranes and is also present to a lesser degree in the brain and other tissues. It preferentially catalyzes cleavage at the amino group of hydrophobic residues of the B-chain of insulin as well as opioid peptides and other biologically active peptides. The enzyme is inhibited primarily by EDTA, phosphoramidon, and thiorphan and is reactivated by zinc. Neprilysin is identical to common acute lymphoblastic leukemia antigen (CALLA Antigen), an important marker in the diagnosis of human acute lymphocytic leukemia. There is no relationship with CALLA PLANT.Oxytocin: A nonapeptide hormone released from the neurohypophysis (PITUITARY GLAND, POSTERIOR). It differs from VASOPRESSIN by two amino acids at residues 3 and 8. Oxytocin acts on SMOOTH MUSCLE CELLS, such as causing UTERINE CONTRACTIONS and MILK EJECTION.Imidazoles: Compounds containing 1,3-diazole, a five membered aromatic ring containing two nitrogen atoms separated by one of the carbons. Chemically reduced ones include IMIDAZOLINES and IMIDAZOLIDINES. Distinguish from 1,2-diazole (PYRAZOLES).Metoclopramide: A dopamine D2 antagonist that is used as an antiemetic.Regional Blood Flow: The flow of BLOOD through or around an organ or region of the body.Plasma Volume: Volume of PLASMA in the circulation. It is usually measured by INDICATOR DILUTION TECHNIQUES.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.Kidney Tubules, Collecting: Straight tubes commencing in the radiate part of the kidney cortex where they receive the curved ends of the distal convoluted tubules. In the medulla the collecting tubules of each pyramid converge to join a central tube (duct of Bellini) which opens on the summit of the papilla.Pyridines: Compounds with a six membered aromatic ring containing NITROGEN. The saturated version is PIPERIDINES.Rats, Inbred SHR: A strain of Rattus norvegicus with elevated blood pressure used as a model for studying hypertension and stroke.TetrazolesImmersion: The placing of a body or a part thereof into a liquid.Receptors, Dopamine D1: A subfamily of G-PROTEIN-COUPLED RECEPTORS that bind the neurotransmitter DOPAMINE and modulate its effects. D1-class receptor genes lack INTRONS, and the receptors stimulate ADENYLYL CYCLASES.Dihydroxyphenylalanine: A beta-hydroxylated derivative of phenylalanine. The D-form of dihydroxyphenylalanine has less physiologic activity than the L-form and is commonly used experimentally to determine whether the pharmacological effects of LEVODOPA are stereospecific.Angiotensin II Type 1 Receptor Blockers: Agents that antagonize ANGIOTENSIN II TYPE 1 RECEPTOR. Included are ANGIOTENSIN II analogs such as SARALASIN and biphenylimidazoles such as LOSARTAN. Some are used as ANTIHYPERTENSIVE AGENTS.Benzimidazoles: Compounds with a BENZENE fused to IMIDAZOLES.Rats, Inbred Strains: Genetically identical individuals developed from brother and sister matings which have been carried out for twenty or more generations or by parent x offspring matings carried out with certain restrictions. This also includes animals with a long history of closed colony breeding.Drinking: The consumption of liquids.Loop of Henle: The U-shaped portion of the renal tubule in the KIDNEY MEDULLA, consisting of a descending limb and an ascending limb. It is situated between the PROXIMAL KIDNEY TUBULE and the DISTAL KIDNEY TUBULE.Cardenolides: C(23)-steroids with methyl groups at C-10 and C-13 and a five-membered lactone at C-17. They are aglycone constituents of CARDIAC GLYCOSIDES and must have at least one double bond in the molecule. The class includes cardadienolides and cardatrienolides. Members include DIGITOXIN and DIGOXIN and their derivatives and the STROPHANTHINS.Metolazone: A quinazoline-sulfonamide derived DIURETIC that functions by inhibiting SODIUM CHLORIDE SYMPORTERS.Extracellular Space: Interstitial space between cells, occupied by INTERSTITIAL FLUID as well as amorphous and fibrous substances. For organisms with a CELL WALL, the extracellular space includes everything outside of the CELL MEMBRANE including the PERIPLASM and the cell wall.Hematocrit: The volume of packed RED BLOOD CELLS in a blood specimen. The volume is measured by centrifugation in a tube with graduated markings, or with automated blood cell counters. It is an indicator of erythrocyte status in disease. For example, ANEMIA shows a low value; POLYCYTHEMIA, a high value.Dopamine: One of the catecholamine NEUROTRANSMITTERS in the brain. It is derived from TYROSINE and is the precursor to NOREPINEPHRINE and EPINEPHRINE. Dopamine is a major transmitter in the extrapyramidal system of the brain, and important in regulating movement. A family of receptors (RECEPTORS, DOPAMINE) mediate its action.NG-Nitroarginine Methyl Ester: A non-selective inhibitor of nitric oxide synthase. It has been used experimentally to induce hypertension.Epithelial Sodium Channels: Sodium channels found on salt-reabsorbing EPITHELIAL CELLS that line the distal NEPHRON; the distal COLON; SALIVARY DUCTS; SWEAT GLANDS; and the LUNG. They are AMILORIDE-sensitive and play a critical role in the control of sodium balance, BLOOD VOLUME, and BLOOD PRESSURE.Rats, Inbred WKY: A strain of Rattus norvegicus used as a normotensive control for the spontaneous hypertensive rats (SHR).Sodium-Potassium-Chloride Symporters: A subclass of symporters that specifically transport SODIUM CHLORIDE and/or POTASSIUM CHLORIDE across cellular membranes in a tightly coupled process.Sodium-Phosphate Cotransporter Proteins, Type II: A family of sodium-phosphate cotransporter proteins with eight transmembrane domains. They are present primarily in the KIDNEY and SMALL INTESTINE and are responsible for renal and small intestinal epithelial transport of phosphate.Hypernatremia: Excessive amount of sodium in the blood. (Dorland, 27th ed)Receptors, Vasopressin: Specific molecular sites or proteins on or in cells to which VASOPRESSINS bind or interact in order to modify the function of the cells. Two types of vasopressin receptor exist, the V1 receptor in the vascular smooth muscle and the V2 receptor in the kidneys. The V1 receptor can be subdivided into V1a and V1b (formerly V3) receptors.Nephrectomy: Excision of kidney.Dose-Response Relationship, Drug: The relationship between the dose of an administered drug and the response of the organism to the drug.Injections, Intraventricular: Injections into the cerebral ventricles.CreatinineSodium-Hydrogen Antiporter: A plasma membrane exchange glycoprotein transporter that functions in intracellular pH regulation, cell volume regulation, and cellular response to many different hormones and mitogens.Inappropriate ADH Syndrome: A condition of HYPONATREMIA and renal salt loss attributed to overexpansion of BODY FLUIDS resulting from sustained release of ANTIDIURETIC HORMONES which stimulates renal resorption of water. It is characterized by normal KIDNEY function, high urine OSMOLALITY, low serum osmolality, and neurological dysfunction. Etiologies include ADH-producing neoplasms, injuries or diseases involving the HYPOTHALAMUS, the PITUITARY GLAND, and the LUNG. This syndrome can also be drug-induced.Imidazoline Receptors: Receptors of CLONIDINE and other IMIDAZOLINES. Activity of the ligands was earlier attributed to ADRENERGIC ALPHA-2 RECEPTORS. Endogenous ligands include AGMATINE, imidazoleacetic acid ribotide, and harman.Kidney Concentrating Ability: The ability of the kidney to excrete in the urine high concentrations of solutes from the blood plasma.Perfusion: Treatment process involving the injection of fluid into an organ or tissue.p-Aminohippuric Acid: The glycine amide of 4-aminobenzoic acid. Its sodium salt is used as a diagnostic aid to measure effective renal plasma flow (ERPF) and excretory capacity.Infusions, Intravenous: The long-term (minutes to hours) administration of a fluid into the vein through venipuncture, either by letting the fluid flow by gravity or by pumping it.Desoxycorticosterone: A steroid metabolite that is the 11-deoxy derivative of CORTICOSTERONE and the 21-hydroxy derivative of PROGESTERONE.Antihypertensive Agents: Drugs used in the treatment of acute or chronic vascular HYPERTENSION regardless of pharmacological mechanism. Among the antihypertensive agents are DIURETICS; (especially DIURETICS, THIAZIDE); ADRENERGIC BETA-ANTAGONISTS; ADRENERGIC ALPHA-ANTAGONISTS; ANGIOTENSIN-CONVERTING ENZYME INHIBITORS; CALCIUM CHANNEL BLOCKERS; GANGLIONIC BLOCKERS; and VASODILATOR AGENTS.Deamino Arginine Vasopressin: A synthetic analog of the pituitary hormone, ARGININE VASOPRESSIN. Its action is mediated by the VASOPRESSIN receptor V2. It has prolonged antidiuretic activity, but little pressor effects. It also modulates levels of circulating FACTOR VIII and VON WILLEBRAND FACTOR.Kinins: A generic term used to describe a group of polypeptides with related chemical structures and pharmacological properties that are widely distributed in nature. These peptides are AUTACOIDS that act locally to produce pain, vasodilatation, increased vascular permeability, and the synthesis of prostaglandins. Thus, they comprise a subset of the large number of mediators that contribute to the inflammatory response. (From Goodman and Gilman's The Pharmacologic Basis of Therapeutics, 8th ed, p588)Pressure: A type of stress exerted uniformly in all directions. Its measure is the force exerted per unit area. (McGraw-Hill Dictionary of Scientific and Technical Terms, 6th ed)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.Chlorides: Inorganic compounds derived from hydrochloric acid that contain the Cl- ion.Water: A clear, odorless, tasteless liquid that is essential for most animal and plant life and is an excellent solvent for many substances. The chemical formula is hydrogen oxide (H2O). (McGraw-Hill Dictionary of Scientific and Technical Terms, 4th ed)Angiotensin-Converting Enzyme Inhibitors: A class of drugs whose main indications are the treatment of hypertension and heart failure. They exert their hemodynamic effect mainly by inhibiting the renin-angiotensin system. They also modulate sympathetic nervous system activity and increase prostaglandin synthesis. They cause mainly vasodilation and mild natriuresis without affecting heart rate and contractility.Benzazepines: Compounds with BENZENE fused to AZEPINES.Rats, Mutant Strains: Rats bearing mutant genes which are phenotypically expressed in the animals.2,3,4,5-Tetrahydro-7,8-dihydroxy-1-phenyl-1H-3-benzazepine: A selective D1 dopamine receptor agonist used primarily as a research tool.Kidney Pelvis: The flattened, funnel-shaped expansion connecting the URETER to the KIDNEY CALICES.