Halothane: A nonflammable, halogenated, hydrocarbon anesthetic that provides relatively rapid induction with little or no excitement. Analgesia may not be adequate. NITROUS OXIDE is often given concomitantly. Because halothane may not produce sufficient muscle relaxation, supplemental neuromuscular blocking agents may be required. (From AMA Drug Evaluations Annual, 1994, p178)Anesthetics, Inhalation: Gases or volatile liquids that vary in the rate at which they induce anesthesia; potency; the degree of circulation, respiratory, or neuromuscular depression they produce; and analgesic effects. Inhalation anesthetics have advantages over intravenous agents in that the depth of anesthesia can be changed rapidly by altering the inhaled concentration. Because of their rapid elimination, any postoperative respiratory depression is of relatively short duration. (From AMA Drug Evaluations Annual, 1994, p173)Anesthesia, Inhalation: Anesthesia caused by the breathing of anesthetic gases or vapors or by insufflating anesthetic gases or vapors into the respiratory tract.Isoflurane: A stable, non-explosive inhalation anesthetic, relatively free from significant side effects.Enflurane: An extremely stable inhalation anesthetic that allows rapid adjustments of anesthesia depth with little change in pulse or respiratory rate.Methyl Ethers: A group of compounds that contain the general formula R-OCH3.Anesthetics: Agents that are capable of inducing a total or partial loss of sensation, especially tactile sensation and pain. They may act to induce general ANESTHESIA, in which an unconscious state is achieved, or may act locally to induce numbness or lack of sensation at a targeted site.Nitrous Oxide: Nitrogen oxide (N2O). A colorless, odorless gas that is used as an anesthetic and analgesic. High concentrations cause a narcotic effect and may replace oxygen, causing death by asphyxia. It is also used as a food aerosol in the preparation of whipping cream.Malignant Hyperthermia: Rapid and excessive rise of temperature accompanied by muscular rigidity following general anesthesia.Trifluoroacetic Acid: A very strong halogenated derivative of acetic acid. It is used in acid catalyzed reactions, especially those where an ester is cleaved in peptide synthesis.Thiopental: A barbiturate that is administered intravenously for the induction of general anesthesia or for the production of complete anesthesia of short duration.EthersDogs: 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)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.Depression, Chemical: The decrease in a measurable parameter of a PHYSIOLOGICAL PROCESS, including cellular, microbial, and plant; immunological, cardiovascular, respiratory, reproductive, urinary, digestive, neural, musculoskeletal, ocular, and skin physiological processes; or METABOLIC PROCESS, including enzymatic and other pharmacological processes, by a drug or other chemical.Ether: A mobile, very volatile, highly flammable liquid used as an inhalation anesthetic and as a solvent for waxes, fats, oils, perfumes, alkaloids, and gums. It is mildly irritating to skin and mucous membranes.Methoxyflurane: An inhalation anesthetic. Currently, methoxyflurane is rarely used for surgical, obstetric, or dental anesthesia. If so employed, it should be administered with NITROUS OXIDE to achieve a relatively light level of anesthesia, and a neuromuscular blocking agent given concurrently to obtain the desired degree of muscular relaxation. (From AMA Drug Evaluations Annual, 1994, p180)Ethyl EthersAnesthesia, General: Procedure in which patients are induced into an unconscious state through use of various medications so that they do not feel pain during surgery.Chlorofluorocarbons: A series of hydrocarbons containing both chlorine and fluorine. These have been used as refrigerants, blowing agents, cleaning fluids, solvents, and as fire extinguishing agents. They have been shown to cause stratospheric ozone depletion and have been banned for many uses.Hydrocarbons, HalogenatedAnesthetics, General: Agents that induce various degrees of analgesia; depression of consciousness, circulation, and respiration; relaxation of skeletal muscle; reduction of reflex activity; and amnesia. There are two types of general anesthetics, inhalation and intravenous. With either type, the arterial concentration of drug required to induce anesthesia varies with the condition of the patient, the desired depth of anesthesia, and the concomitant use of other drugs. (From AMA Drug Evaluations Annual, 1994, p.173)Pentobarbital: A short-acting barbiturate that is effective as a sedative and hypnotic (but not as an anti-anxiety) agent and is usually given orally. It is prescribed more frequently for sleep induction than for sedation but, like similar agents, may lose its effectiveness by the second week of continued administration. (From AMA Drug Evaluations Annual, 1994, p236)Dose-Response Relationship, Drug: The relationship between the dose of an administered drug and the response of the organism to the drug.Drug-Induced Liver Injury: A spectrum of clinical liver diseases ranging from mild biochemical abnormalities to ACUTE LIVER FAILURE, caused by drugs, drug metabolites, and chemicals from the environment.Succinylcholine: A quaternary skeletal muscle relaxant usually used in the form of its bromide, chloride, or iodide. It is a depolarizing relaxant, acting in about 30 seconds and with a duration of effect averaging three to five minutes. Succinylcholine is used in surgical, anesthetic, and other procedures in which a brief period of muscle relaxation is called for.Respiration: The act of breathing with the LUNGS, consisting of INHALATION, or the taking into the lungs of the ambient air, and of EXHALATION, or the expelling of the modified air which contains more CARBON DIOXIDE than the air taken in (Blakiston's Gould Medical Dictionary, 4th ed.). This does not include tissue respiration (= OXYGEN CONSUMPTION) or cell respiration (= CELL RESPIRATION).Hypotension, Controlled: Procedure in which arterial blood pressure is intentionally reduced in order to control blood loss during surgery. This procedure is performed either pharmacologically or by pre-surgical removal of blood.Fluoroacetates: Derivatives of acetic acid with one or more fluorines attached. They are almost odorless, difficult to detect chemically, and very stable. The acid itself, as well as the derivatives that are broken down in the body to the acid, are highly toxic substances, behaving as convulsant poisons with a delayed action. (From Miall's Dictionary of Chemistry, 5th ed)Thiamylal: A barbiturate that is administered intravenously for the production of complete anesthesia of short duration, for the induction of general anesthesia, or for inducing a hypnotic state. (From Martindale, The Extra Pharmacopoeia, 30th ed, p919)Anesthesia, IntratrachealElectronic Mail: Messages between computer users via COMPUTER COMMUNICATION NETWORKS. This feature duplicates most of the features of paper mail, such as forwarding, multiple copies, and attachments of images and other file types, but with a speed advantage. The term also refers to an individual message sent in this way.Food Dispensers, Automatic: Mechanical food dispensing machines.Editorial Policies: The guidelines and policy statements set forth by the editor(s) or editorial board of a publication.Authorship: The profession of writing. Also the identity of the writer as the creator of a literary production.Periodicals as Topic: A publication issued at stated, more or less regular, intervals.Postal Service: The functions and activities carried out by the U.S. Postal Service, foreign postal services, and private postal services such as Federal Express.Internet: A loose confederation of computer communication networks around the world. The networks that make up the Internet are connected through several backbone networks. The Internet grew out of the US Government ARPAnet project and was designed to facilitate information exchange.Receptors, Nicotinic: One of the two major classes of cholinergic receptors. Nicotinic receptors were originally distinguished by their preference for NICOTINE over MUSCARINE. They are generally divided into muscle-type and neuronal-type (previously ganglionic) based on pharmacology, and subunit composition of the receptors.Ion Channels: Gated, ion-selective glycoproteins that traverse membranes. The stimulus for ION CHANNEL GATING can be due to a variety of stimuli such as LIGANDS, a TRANSMEMBRANE POTENTIAL DIFFERENCE, mechanical deformation or through INTRACELLULAR SIGNALING PEPTIDES AND PROTEINS.Receptors, Cholinergic: Cell surface proteins that bind acetylcholine with high affinity and trigger intracellular changes influencing the behavior of cells. Cholinergic receptors are divided into two major classes, muscarinic and nicotinic, based originally on their affinity for nicotine and muscarine. Each group is further subdivided based on pharmacology, location, mode of action, and/or molecular biology.Membrane Lipids: Lipids, predominantly phospholipids, cholesterol and small amounts of glycolipids found in membranes including cellular and intracellular membranes. These lipids may be arranged in bilayers in the membranes with integral proteins between the layers and peripheral proteins attached to the outside. Membrane lipids are required for active transport, several enzymatic activities and membrane formation.Xenopus laevis: The commonest and widest ranging species of the clawed "frog" (Xenopus) in Africa. This species is used extensively in research. There is now a significant population in California derived from escaped laboratory animals.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.Hepatic Insufficiency: Conditions in which the LIVER functions fall below the normal ranges. Severe hepatic insufficiency may cause LIVER FAILURE or DEATH. Treatment may include LIVER TRANSPLANTATION.Drug Interactions: The action of a drug that may affect the activity, metabolism, or toxicity of another drug.Product Labeling: Use of written, printed, or graphic materials upon or accompanying a product or its container or wrapper. It includes purpose, effect, description, directions, hazards, warnings, and other relevant information.Health Resources: Available manpower, facilities, revenue, equipment, and supplies to produce requisite health care and services.United States Health Resources and Services Administration: A component of the PUBLIC HEALTH SERVICE that provides leadership related to the delivery of health services and the requirements for and distribution of health resources, including manpower training.Caffeine: A methylxanthine naturally occurring in some beverages and also used as a pharmacological agent. Caffeine's most notable pharmacological effect is as a central nervous system stimulant, increasing alertness and producing agitation. It also relaxes SMOOTH MUSCLE, stimulates CARDIAC MUSCLE, stimulates DIURESIS, and appears to be useful in the treatment of some types of headache. Several cellular actions of caffeine have been observed, but it is not entirely clear how each contributes to its pharmacological profile. Among the most important are inhibition of cyclic nucleotide PHOSPHODIESTERASES, antagonism of ADENOSINE RECEPTORS, and modulation of intracellular calcium handling.Atmosphere Exposure Chambers: Experimental devices used in inhalation studies in which a person or animal is either partially or completely immersed in a chemically controlled atmosphere.Inhalation Exposure: The exposure to potentially harmful chemical, physical, or biological agents by inhaling them.Rats, Inbred F344Administration, Inhalation: The administration of drugs by the respiratory route. It includes insufflation into the respiratory tract.Toxicity Tests, Chronic: Experiments designed to determine the potential toxic effects of a long-term exposure to a chemical or chemicals.

Mutation screening of the RYR1 gene and identification of two novel mutations in Italian malignant hyperthermia families. (1/1763)

Point mutations in the ryanodine receptor (RYR1) gene are associated with malignant hyperthermia, an autosomal dominant disorder triggered in susceptible people (MHS) by volatile anaesthetics and depolarising skeletal muscle relaxants. To date, 17 missense point mutations have been identified in the human RYR1 gene by screening of the cDNA obtained from muscle biopsies. Here we report single strand conformation polymorphism (SSCP) screening for nine of the most frequent RYR1 mutations using genomic DNA isolated from MHS patients. In addition, the Argl63Cys mutation was analysed by restriction enzyme digestion. We analysed 57 unrelated patients and detected seven of the known RYR1 point mutations. Furthermore, we found a new mutation, Arg2454His, segregating with the MHS phenotype in a large pedigree and a novel amino acid substitution at position 2436 in another patient, indicating a 15.8% frequency of these mutations in Italian patients. A new polymorphic site in intron 16 that causes the substitution of a G at position -7 with a C residue was identified.  (+info)

A neomorphic syntaxin mutation blocks volatile-anesthetic action in Caenorhabditis elegans. (2/1763)

The molecular mechanisms underlying general anesthesia are unknown. For volatile general anesthetics (VAs), indirect evidence for both lipid and protein targets has been found. However, no in vivo data have implicated clearly any particular lipid or protein in the control of sensitivity to clinical concentrations of VAs. Genetics provides one approach toward identifying these mechanisms, but genes strongly regulating sensitivity to clinical concentrations of VAs have not been identified. By screening existing mutants of the nematode Caenorhabditis elegans, we found that a mutation in the neuronal syntaxin gene dominantly conferred resistance to the VAs isoflurane and halothane. By contrast, other mutations in syntaxin and in the syntaxin-binding proteins synaptobrevin and SNAP-25 produced VA hypersensitivity. The syntaxin allelic variation was striking, particularly for isoflurane, where a 33-fold range of sensitivities was seen. Both the resistant and hypersensitive mutations decrease synaptic transmission; thus, the indirect effect of reducing neurotransmission does not explain the VA resistance. As assessed by pharmacological criteria, halothane and isoflurane themselves reduced cholinergic transmission, and the presynaptic anesthetic effect was blocked by the resistant syntaxin mutation. A single gene mutation conferring high-level resistance to VAs is inconsistent with nonspecific membrane-perturbation theories of anesthesia. The genetic and pharmacological data suggest that the resistant syntaxin mutant directly blocks VA binding to or efficacy against presynaptic targets that mediate anesthetic behavioral effects. Syntaxin and syntaxin-binding proteins are candidate anesthetic targets.  (+info)

Functional brain imaging during anesthesia in humans: effects of halothane on global and regional cerebral glucose metabolism. (3/1763)

BACKGROUND: Propofol and isoflurane anesthesia were studied previously with functional brain imaging in humans to begin identifying key brain areas involved with mediating anesthetic-induced unconsciousness. The authors describe an additional positron emission tomography study of halothane's in vivo cerebral metabolic effects. METHODS: Five male volunteers each underwent two positron emission tomography scans. One scan assessed awake-baseline metabolism, and the other scan assessed metabolism during halothane anesthesia titrated to the point of unresponsiveness (mean +/- SD, expired = 0.7+/-0.2%). Scans were obtained using a GE2048 scanner and the F-18 fluorodeoxyglucose technique. Regions of interest were analyzed for changes in both absolute and relative glucose metabolism. In addition, relative changes in metabolism were evaluated using statistical parametric mapping. RESULTS: Awake whole-brain metabolism averaged 6.3+/-1.2 mg x 100 g(-1) x min(-1) (mean +/- SD). Halothane reduced metabolism 40+/-9% to 3.7+/-0.6 mg x 100 g(-1) x min(-1) (P< or =0.005). Regional metabolism did not increase in any brain areas for any volunteer. The statistical parametric mapping analysis revealed significantly less relative metabolism in the basal forebrain, thalamus, limbic system, cerebellum, and occiput during halothane anesthesia. CONCLUSIONS: Halothane caused a global whole-brain metabolic reduction with significant shifts in regional metabolism. Comparisons with previous studies reveal similar absolute and relative metabolic effects for halothane and isoflurane. Propofol, however, was associated with larger absolute metabolic reductions, suppression of relative cortical metabolism more than either inhalational agent, and significantly less suppression of relative basal ganglia and midbrain metabolism.  (+info)

Primary and secondary hyperalgesia in a rat model for human postoperative pain. (4/1763)

BACKGROUND: Previously, the authors developed and characterized a rat model for postoperative pain to learn more about pain produced by incisions. In this study, the responses to heat and mechanical stimuli were evaluated directly on or adjacent to the incision and at varying distances from the incision. METHODS: Rats were anesthetized with halothane and incisions were made at different locations in the plantar aspect of the foot. The response frequency to a blunt mechanical stimulus, the withdrawal threshold to von Frey filaments (15-522 mN), and the withdrawal latency to radiant heat were measured. Rats were tested before surgery, 2 h later, and then daily through postoperative day 9. RESULTS: After plantar incision, persistent hyperalgesia was observed immediately adjacent to or directly on the incision to punctate and blunt mechanical stimuli, respectively. The withdrawal threshold to punctate stimuli applied 1 cm from the incision was decreased through postoperative day 1. In a transitional area, between the distant and adjacent sites, the withdrawal threshold was intermediate and the duration of hyperalgesia was transient. Heat hyperalgesia was persistent but present when the stimulus was applied to the site of injury but not to a distant site. CONCLUSION: Robust primary hyperalgesia to punctate and blunt mechanical stimuli was present. Hyperalgesia distant to the wound, or secondary hyperalgesia, occurred in response to punctate mechanical stimuli, was short-lived, and required greater forces. These results suggest that the most persistent pain behaviors in this model are largely primary hyperalgesia.  (+info)

Halothane, an inhalational anesthetic agent, increases folding stability of serum albumin. (5/1763)

Inhalational anesthetic agents are known to alter protein function, but the nature of the interactions underlying these effects remains poorly understood. We have used differential scanning calorimetry to study the effects of the anesthetic agent halothane on the thermally induced unfolding transition of bovine serum albumin. We find that halothane (0.6-10 mM) stabilizes the folded state of this protein, increasing its transition midpoint temperature from 62 to 71 degrees C. Binding of halothane to the native state of serum albumin thus outweighs any non-specific interactions between the thermally unfolded state of serum albumin and halothane in this concentration range. Based on the average enthalpy change DeltaH for unfolding of 170 kcal/mol, the increase from 62 to 71 degrees C corresponds to an additional Gibbs energy of stabilization (DeltaDeltaG) due to halothane of more than 4 kcal/mol. Analysis of the dependence of DeltaDeltaG on halothane concentration shows that thermal unfolding of a bovine serum albumin molecule is linked to the dissociation of about one halothane molecule at lower halothane concentrations and about six at higher halothane concentrations. Serum albumin is the first protein that has been shown to be stabilized by an inhalational anesthetic.  (+info)

A mutation in the transmembrane/luminal domain of the ryanodine receptor is associated with abnormal Ca2+ release channel function and severe central core disease. (6/1763)

Central core disease is a rare, nonprogressive myopathy that is characterized by hypotonia and proximal muscle weakness. In a large Mexican kindred with an unusually severe and highly penetrant form of the disorder, DNA sequencing identified an I4898T mutation in the C-terminal transmembrane/luminal region of the RyR1 protein that constitutes the skeletal muscle ryanodine receptor. All previously reported RYR1 mutations are located either in the cytoplasmic N terminus or in a central cytoplasmic region of the 5,038-aa protein. The I4898T mutation was introduced into a rabbit RYR1 cDNA and expressed in HEK-293 cells. The response of the mutant RyR1 Ca2+ channel to the agonists halothane and caffeine in a Ca2+ photometry assay was completely abolished. Coexpression of normal and mutant RYR1 cDNAs in a 1:1 ratio, however, produced RyR1 channels with normal halothane and caffeine sensitivities, but maximal levels of Ca2+ release were reduced by 67%. [3H]Ryanodine binding indicated that the heterozygous channel is activated by Ca2+ concentrations 4-fold lower than normal. Single-cell analysis of cotransfected cells showed a significantly increased resting cytoplasmic Ca2+ level and a significantly reduced luminal Ca2+ level. These data are indicative of a leaky channel, possibly caused by a reduction in the Ca2+ concentration required for channel activation. Comparison with two other coexpressed mutant/normal channels suggests that the I4898T mutation produces one of the most abnormal RyR1 channels yet investigated, and this level of abnormality is reflected in the severe and penetrant phenotype of affected central core disease individuals.  (+info)

Effects of the halothane genotype and slaughter weight on texture of pork. (7/1763)

The objective of this study was to investigate the effects of the halothane (HAL) genotype, slaughter weight (SW), and the HAL x SW interaction on compositional and textural traits of raw and cooked pork. Pigs were bred to exhibit one of the three HAL genotypes (NN, Nn, and nn) with otherwise equivalent genomes. The nn halothane reactors are known to typically produce PSE pork, whereas NN pigs do not typically produce PSE pork. Pietrain x Large White gilts and boars, all with verified Nn genotype (by DNA test), were mated to obtain F2 littermates of the three HAL genotypes. These pigs were slaughtered at either 101 +/- 3 ("light") or 127 +/- 3 ("heavy") kg BW and were evaluated for longissimus muscle traits. The pH at .5 h after death (pH1) was 6.35, 6.13, and 5.68 in NN, Nn, and nn pigs, respectively. Sarcomere length was greater in nn than in NN and Nn pigs (1.94 vs 1.83 and 1.85 microm, respectively). Mechanical resistance was higher in nn than in NN pigs for both raw and cooked meat. Meat from nn pigs was judged by a trained panel to be less rough, more cohesive, harder, more fibrous, less granular, more elastic, and less easy to swallow than meat from NN pigs. For most traits under study, the heterozygotes were intermediate between the homozygotes but closer to NN than to nn pigs. Muscle from heavy pigs had longer sarcomeres and less moisture than muscle from light pigs. The n allele of the HAL gene unfavorably affects pork texture, and this effect is maintained throughout the range of 101 to 127 kg BW.  (+info)

Halothane effect on formalin-induced paw edema and flinching in rat. (8/1763)

The formalin test is a model of injury-produced inflammatory pain. Anesthetics, in clinically relevant concentrations, affect neutrophils and immune suppression. This study was to determine whether halothane reliably inhibits inflammatory reaction and formalin induced pain behavior or does not. Rats were exposed to 100% oxygen (control) or halothane, respectively for 30 min and then 24 hr later five percent formalin test was assessed. The base values of the paw's diameter were obtained earlier, and then formalin induced edema was assessed by measuring diameters of the injected paws at 5 min, 1 hr, 4 hr and 24 hr after the injection. Nociceptive behavior was quantified by counting the number of times with the paw flinched at 5 min intervals for 60 min. The diameters of edema in the halothane group lessened more than those in the oxygen group at 1 and 24 hr in each following of the injection (p<0.05). The rats pre-administered with oxygen or halothane were similar appearances in nociceptive behaviors. It suggests that halothane anesthesia might inhibit slightly the inflammatory reaction with the formalin-induced edema but might not inhibit the formalin-induced pain behavior in the event of pre-administration halothane 24 hr earlier before the formalin test of rat.  (+info)

  • This process stimulates the formation of antibodies, which, upon reexposure to halothane (or enflurane, isoflurane, or desflurane), initiates an immune-mediated necrosis. (medscape.com)
  • Comparison of the effects of sub-hypnotic concentrations of propofol and halothane on the acute ventilatory response to hypoxia. (ox.ac.uk)
  • To compare the effects of sub-anaesthetic concentrations of propofol and halothane on the respiratory control system, we have studied the acute ventilatory response to isocapnic hypoxia (AHVR) in 12 adults with and without three different concentrations of propofol and halothane. (ox.ac.uk)
  • In contrast, halothane shortened the burst durations of both channel types in a concentration-dependent manner. (pnas.org)
  • Halothane is miscible with alcohol , chloroform , ether, and other fat solvents. (rxlist.com)
  • Fluothane (halothane) is nonflammable, and its vapors mixed with oxygen in proportions from 0.5 to 50% (v/v) are not explosive. (rxlist.com)
  • As with other agents of this type, halothane anaesthesia has been shown to trigger a skeletal muscle hypermetabolic state leading to high oxygen demand and the clinical syndrome known as malignant hyperthermia (MH). (rxlist.com)
  • Stability of Fluothane (halothane) is maintained by the addition of 0.01% thymol (w/w), up to 0.00025% ammonia (w/w). (rxlist.com)
  • Feng D, Wang Y, Xu Y, Luo Q, Lan B, Xu L. Interleukin 10 deficiency exacerbates halothane induced liver injury by increasing interleukin 8 expression and neutrophil infiltration. (medscape.com)
  • Kobayashi E, Kobayashi M, Tsuneyama K, Fukami T, Nakajima M, Yokoi T. Halothane-induced liver injury is mediated by interleukin-17 in mice. (medscape.com)
  • This distribution was maintained during exposure to halothane and its washout. (pnas.org)
  • Type I (mild) halothane hepatotoxicity occurs within hours of halothane exposure. (medscape.com)
  • Type II (fulminant) halothane hepatotoxicity usually occurs 5-7 days following exposure, although it can be delayed by up to 4 weeks. (medscape.com)
  • No evidence of an exposure related change in physical appearance or behavior of the rats exposed to N2O and halothane was noted. (cdc.gov)
  • such materials will deteriorate rapidly in contact with Fluothane (halothane) vapor or liquid. (rxlist.com)
  • Thymol does not volatilize along with Fluothane (halothane) and, therefore, accumulates in the vaporizer and may, in time, impart a yellow color to the remaining liquid or to wicks in vaporizers. (rxlist.com)
  • Male and female Fischer-344 rats were exposed to N2O and halothane mixtures in inhalation chambers, 7 hours/day, 5 days/week for 104 weeks. (cdc.gov)
  • An increase in the occurrence of neoplasia in general was not seen as a result of the combined exposures to N2O and halothane. (cdc.gov)
  • Group 1 was control group exposed only to room air, group 2 was exposed to 50 parts per million (ppm) N2O and 1ppm halothane, and group 3 was exposed to 500ppm N2O and 10ppm halothane. (cdc.gov)
  • (1) present the clinically useful results of their research of the effect of halothane on hemodynamic variables during induction of anesthesia in infants after a variable preoperative fast. (lww.com)
  • The effect of halothane on the action of alcuronium on neuromuscular transmission was studied in the intact dog. (uzh.ch)
  • Methods The authors evaluated the effect of halothane on synaptic transmission at the larval neuromuscular junction in wild-type (Ore-R) and halothane-resistant (har) mutants of Drosophila melanogaster. (ovid.com)
  • Studies of the effect of halothane on airway smooth muscle have used pulmonary resistance as an index of airway caliber. (elsevier.com)
  • The authors conclude that changes in R(L) during halothane administration are caused not only by changes in airway caliber, as previously assumed, but also reflect a significant effect of halothane on lung tissue pressure-volume hysteresis. (elsevier.com)
  • In an effort to identify one possible site of anesthetic action, the effect of halothane on the uptake of 5-HT was studied in synaptosomes isolated from the brain of rat. (elsevier.com)
  • The mechanism of the direct relaxing effect of halothane on airway smooth muscle may involve a decrease in 1) cytosolic calcium concentration ([Ca2+]i) and/or 2) the force produced for a given [Ca2+]i (i.e., the "sensitivity" of the myofibrillar contractile system to Ca2+). (uab.edu)
  • Tao, F & Johns, RA 2008, ' Effect of disrupting N-methyl-D-aspartate receptor-postsynaptic density protein-95 interactions on the threshold for halothane anesthesia in mice ', Anesthesiology , vol. 108, no. 5, pp. 882-887. (elsevier.com)
  • Todd, MM , Weeks, JB & Warner, DS 1993, ' A focal cryogenic brain lesion does not reduce the minimum alveolar concentration for halothane in rats ', Anesthesiology , vol. 79, no. 1, pp. 139-143. (umn.edu)
  • Inhalation toxicity study of nitrous oxide and halothane in rats. (cdc.gov)
  • The chronic toxicity of a combination of nitrous-oxide (10024972) (N2O) and halothane (151677) was investigated in rats. (cdc.gov)
  • Male and female Fischer-344 rats were exposed to N2O and halothane mixtures in inhalation chambers, 7 hours/day, 5 days/week for 104 weeks. (cdc.gov)
  • Significant levels of trifluoroacetyl protein antigens were generated when human liver microsomes, and also microsomes from livers of rats pre-treated with isoniazid, phenobarbital or beta-naphtoflavone, were incubated with halothane plus a nicotinamide adenine dinucleotidephosphate (NADPH) generating system. (sigmaaldrich.com)
  • Time course of 72-kilodalton heat shock protein induction and appearance of trifluoroacetyl adducts in livers of halothane-exposed rats. (aspetjournals.org)
  • Ten phenobarbital-pretreated rats were exposed for 2 hr to 1% halothane in 10% O2 and 10 were exposed to 1% halothane in 20% O2. (aspetjournals.org)
  • Thin sections stained with hematoxylin and eosin demonstrated that centrilobular lesions occurred at 6 hr and became extensive at 24 hr in rats pretreated with phenobarbital and exposed to 1% halothane in 10% O2. (aspetjournals.org)
  • Trifluoroacetylated adducts appeared in all rats exposed to halothane by 2 hr, lasted until 6 hr, and then diminished by 24 hr. (aspetjournals.org)
  • In contrast, HSP72 was induced only in the rats pretreated with phenobarbital and exposed to 1% halothane in 10% O2. (aspetjournals.org)
  • 2. At this concentration of halothane uptake of oxygen was inhibited in livers from both fed and starved rats. (biochemj.org)
  • 4. In livers of starved rats the rate of gluconeogenesis from lactate was decreased by halothane to 30% of the control rate. (biochemj.org)
  • The effects of anesthesia with either halothane or isoflurane were also compared on stress-induced learned helplessness behavior in rats and mice. (umaryland.edu)
  • Results: Isoflurane, but not halothane, anesthesia elicited a dose-dependent cortical burst suppression EEG in rats and mice. (umaryland.edu)
  • Methods: Rats were anesthetized with isoflurane (n = 8) or halothane (n = 8) and a laminectomy performed. (elsevier.com)
  • To determine whether this was true with other anesthetics, the authors determined the minimum alveolar concentration (MAC) for halothane in normothermic, normocarbic ventilated Sprague-Dawley rats previously subjected to a freezing injury of the parietal cortex. (umn.edu)
  • Methods: Injury was produced in halothane-anesthetized rats by applying a cold (-70° C), 4-mm-diameter brass rod to the exposed dura for 5 or 15 s. (umn.edu)
  • In contrast, no differences were seen in rats when cortical depolarization (instead of the electroencephalogram) was used as the ischemic marker during equi-MAC isoflurane-N2O and halothane-N2O anesthesia. (duke.edu)
  • CONCLUSIONS: The CBF threshold for cortical depolarization as measured by laser-Doppler flowmetry did not differ significantly between halothane-N2O- and isoflurane-N2O-anesthetized rats. (duke.edu)
  • Fluothane (halothane) is nonflammable, and its vapors mixed with oxygen in proportions from 0.5 to 50% (v/v) are not explosive. (rxlist.com)
  • Fluothane (halothane) does not decompose in contact with warm soda lime. (rxlist.com)
  • such materials will deteriorate rapidly in contact with Fluothane (halothane) vapor or liquid. (rxlist.com)
  • Stability of Fluothane (halothane) is maintained by the addition of 0.01% thymol (w/w), up to 0.00025% ammonia (w/w). (rxlist.com)
  • Fluothane (halothane, USP) is indicated for the induction and maintenance of general anesthesia . (rxlist.com)
  • Fluothane (halothane) may be administered by the nonrebreathing technique, partial rebreathing, or closed technique. (rxlist.com)
  • Fluothane (halothane) may be administered with either oxygen or a mixture of oxygen and nitrous oxide . (rxlist.com)
  • Fluothane (halothane) should not be kept indefinitely in vaporizer bottles not specifically designed for its use. (rxlist.com)
  • Thymol does not volatilize along with Fluothane (halothane) and, therefore, accumulates in the vaporizer and may, in time, impart a yellow color to the remaining liquid or to wicks in vaporizers. (rxlist.com)
  • The development of such discoloration may be used as an indicator that the vaporizer should be drained and cleaned, and the discolored Fluothane (halothane, USP) discarded. (rxlist.com)
  • Fluothane® (halothane, USP) is available in unit packages of 125 mL (NDC 0046-3125-81) and 250 mL (NDC 0046-3125-82) of halothane, USP, stabilized with 0.01% thymol (w/w) and up to 0.00025% ammonia (w/w). (rxlist.com)
  • Cardiac arrhythmias, in particular ventricular arrthymias, have been reported as being very common during FLUOTHANE (halothane) use. (rxlist.com)
  • Malignant hyperthermia has been reported in patients given halothane with and without suxam-ethonium (succinylcholine). (brainkart.com)
  • The literature is briefly reviewed and an account of the present status of malignant hyperthermia (porcine stress syndrome) in Ontario boars using the halothane or halothane/succinylcholine screening tests is presented. (islandscholar.ca)
  • It is suggested that the prevalence of malignant hyperthermia in Ontario breeding herds is much higher than was originally thought and that the halothane challenge is an inadequate screening test for this trait if the intention is to remove the genetic trait from the breeding herd. (islandscholar.ca)
  • BACKGROUND: Mice lacking calsequestrin-1 (CASQ1-null), a Ca-binding protein that modulates the activity of Ca release in the skeletal muscle, exhibit lethal hypermetabolic episodes that resemble malignant hyperthermia in humans when exposed to halothane or heat stress. (unich.it)
  • Conclusions Halothane depresses synaptic transmission at the wild-type Drosophila neuromuscular junction, most likely by affecting presynaptic properties. (ovid.com)
  • CONCLUSIONS: By disrupting PSD-95 PDZ2 domain-mediated protein interactions, intraperitoneal injection of cell-permeant fusion peptide Tat-PSD-95 PDZ2 dose-dependently reduces the threshold for halothane anesthesia. (elsevier.com)
  • Glycopyrrolate administration was associated with impaction of the large colon in I horse and low intestinal auscultation scores lasting 24 hours in 3 horses.Conclusions and Clinical Relevance-The positive chronotropic effects of glycopyrrolate resulted in improvement of hemodynamic function in horses anesthetized with halothane and xylazine. (unesp.br)
  • Conclusions: These results indicate that a focal cortical brain injury that has no obvious neurologic or behavioral effects in the awake rat does not alter halothane requirements. (umn.edu)
  • The sarcoplasmic reticulum Ca 2+ storage peaked in the myotubes treated with 0.01 μmol/L simvastatin, but it decreased when cells were treated with higher doses of simvastatin (0.1-5.0 μmol/L).Conclusions The myotoxic side effect of simvastatin was found to change the sensitivity of myotubes in response to high-dose caffeine and halothane. (cams.cn)
  • Hepatic blood flow (HBF) (assessed by plasma clearance and hepatic extraction of indocyanine green), cardiac index, and hepatic venous oxygen saturation were measured in patients before and after induction of anesthesia with thiopental, fentanyl, and N2O, and again during halothane (1 MAC)-N2O (n = 5) or isoflurane (1 MAC)-N2O (n = 6) anesthesia before the start of surgery. (semanticscholar.org)
  • One of the most dreaded Halothane Complications is hepatic injury. (anesthesiageneral.com)
  • Halothane Complications may occur due to decreased hepatic blood flow and reductive biotransformation. (anesthesiageneral.com)
  • Hepatic injury from halogenated inhalational agents was first recognized with chloroform, with more hesitation with halothane, and more hesitantly still with the newer agents as they have been introduced in succession. (lww.com)
  • Covalent binding of reactive halothane biotransformation intermediates to hepatic protein paralleled plasma TFA. (elsevier.com)
  • 10. Effects on gluconeogenesis similar to those of halothane occurred in livers exposed to the anaesthetic methoxyflurane, although normal rates were not restored on withdrawal of the drug. (biochemj.org)
  • Carpenter and coworkers found that as much as half of the halothane and three quarters of the methoxyflurane that are taken up undergo biodegradation. (anesthesiageneral.com)
  • The effects of halothane on EPSC amplitude and kinetics were analyzed at various membrane potentials and were compared with its effects on currents evoked by exogenously applied glutamatergic agonists. (nih.gov)
  • ABSTRACT The anaesthetic agent halothane is still widely used in developing countries including the Islamic Republic of Iran because of its low price. (who.int)
  • abstract = "Background: Isoflurane and halothane act in the spinal cord to blunt ascending transmission of impulses to the brain resulting from noxious stimulation. (elsevier.com)
  • Objective To determine whether the myotoxic side effects of statin simvastatin affect skeletal muscle's sensitivity to caffeine and halothane.Methods Primary cultured neonate rat skeletal myotubes were treated with 0.01-5.0 μmol/L simvastatin for 48 hours. (cams.cn)
  • Low-dose Simvastatin Increases Skeletal Muscle Sensitivity to Caffeine and Halothane[J].Chinese Medical Sciences Journal, 2016, 31(2): 107-115. (cams.cn)
  • Comprehensive cost-effectiveness studies are needed before a decision is made on complete replacement of halothane with other anaesthetics. (who.int)
  • The distribution of halothane is to lungs, VRG organs, muscle, fat around VRG organs and finally peripheral fat. (anesthesiageneral.com)
  • Chemically, halothane is an alkyl halide (not an ether like many other anesthetics). (wikipedia.org)
  • Using excessive doses of loperamide can cause serious and potentially fatal complications such as irregular heart rhythm and cardiac arrest, and the risk may be increased when combined with other medications that can also cause cardiac problems such as halothane. (drugs.com)
  • Simvastatin did not change myotube's sensitivity to low doses of caffeine (0.625-2.5 mmol/L) or halothane (1.0-5.0 mmol/L). In response to high-dose caffeine (10.0 mmol/L, 20.0 mmol/L) and halothane (20.0 mmol/L, 40.0 mmol/L), myotubes treated with 0.01 μmol/L simvastatin showed a significant increase in sensitivity, but those treated with 1.0 μmol/L and 5.0 μmol/L simvastatin showed a significant decrease. (cams.cn)
  • The doses achieved experimentally were 0.01, 0.06, 0.13 and 0.26 of the EC50 for propofol and 0, 0.05, 0.11 and 0.20 MAC for halothane. (ox.ac.uk)
  • 8. The results suggest that at lower doses (0.47 and 1.89 mM) halothane specifically and reversibly stimulates Ca2+ efflux via the RRed-sensitive SR Ca2(+)-release channel by a mechanism which does not require the presence of nucleotides or relatively high [Ca2+]. (edu.au)
  • At higher doses (greater than 5 mM) halothane irreversibly damages the SR membrane, presumably by disrupting the lipid bilayer. (edu.au)
  • In contrast, an 18.0% prevalence rate was determined using halothane/succinylcholine challenge on 123 boars. (islandscholar.ca)
  • When dose was low, sensitivity increased mainly because of increased Ca 2+ content in the sarcoplasmic reticulum, which might explain why some individuals with statin-induced myotoxic symptoms may show positive caffeine-halothane contracture test results. (cams.cn)
  • Halothane inhibited veratridine-evoked glutamate release from synaptosomes with comparable potency (IC50 = 0.67 mM). (cornell.edu)
  • Halothane was first synthesized by C. W. Suckling of Imperial Chemical Industries in 1951 in Widnes and was first used clinically by M. Johnstone in Manchester in 1956. (wikipedia.org)
  • The absence of an effect by halothane in the har mutants provides evidence that the depression of presynaptic function at the glutamate-mediated synapses is an important contributor to the way halothane alters the responsiveness of the whole animal. (ovid.com)
  • Dominguez, CL , Barter, LS & Antognini, JF 2005, ' Intrathecal picrotoxin minimally alters electroencephalographic responses to noxious stimulation during halothane and isoflurane anesthesia ', Acta Anaesthesiologica Scandinavica , vol. 49, no. 6, pp. 763-770. (elsevier.com)
  • 6. During gluconeogenesis from 10m m -lactate the tissue content of ATP was decreased by 50%, glutamate by 50% and 2-oxoglutarate was decreased eightfold in the halothane-exposed livers. (biochemj.org)
  • The miniature excitatory junctional current decay time constant, thought to reflect the kinetic properties of junctional glutamate receptor channels, was not changed by halothane in either the Ore-R strain or the har mutants. (ovid.com)
  • Methods and Results - This study investigated the influence of sex on drug-induced polymorphic ventricular tachycardia (PVT) in Langendorff-perfused male and female mice hearts (n=54) by injecting a bolus of halothane (1.75 mmol/L) in the perfusate while recording ECGs or optical action potentials (APs). (ahajournals.org)
  • These metabolic dynamics should be considered in studies of other organohalogens, including the new refrigerants that are structurally similar to halothane. (elsevier.com)
  • Because halothane may not produce sufficient muscle relaxation, supplemental neuromuscular blocking agents may be required. (curehunter.com)
  • Halothane potentiates the effect of neuromuscular blocking agents. (brainkart.com)
  • Halothane sensitises the heart to catecholamines, so it is liable to cause cardiac arrhythmias, occasionally fatal, particularly if hypercapnia has been allowed to develop. (wikipedia.org)
  • Other agonists linked to cardiac phospholipase C activation, including endothelin 1 (40 nM) and the muscarinic agonist carbamylcholine (1 mM), also decreased conduction velocity in fibers exposed to halothane. (asahq.org)
  • The charming lady anesthetist in Tartu was the only person who I met who used halothane during general anesthesia for Caesarean Section. (yourdictionary.com)