Biomaterial Database

Halothane inhibits hypoxic pulmonary vasoconstriction in the presence of cyclooxygenase blockade. 1990

D Johnson, and I Mayers, and T Hurst

Department of Anaesthesia, University Hospital, University of Saskatchewan, Saskatoon, Canada.

Using an isolated lung the effects of halothane on hypoxic pulmonary vasoconstriction (HPV) were studied in the presence of cyclooxygenase blockade. The pulmonary vasculature can be divided into arterial, middle and venous segment resistances. Analysis of the vascular pressure-flow relationship further separates resistance into a flow dependent resistance (1/slope) and a zero-flow pressure intercept (PCRIT). We ventilated six lobes with control (35 per cent O2) and hypoxic (three per cent O2) gas mixtures with the addition of either 0, 0.5, 1.0, or 2.0 per cent halothane. We found that after addition of indomethacin (5 mg.kg-1), ventilation with three per cent O2 increased total resistance by 87 per cent over baseline with the increase primarily in the middle vascular segment. During normoxic ventilation PCRIT was 7.9 cm H2O and this increased significantly with hypoxia to 11.5 cm H2O). Only 2.0 per cent halothane blocked the increases in middle segment resistance and in PCRIT. We conclude that following cyclooxygenase blockade, halothane inhibits HPV by acting on middle segment vessels.

UI	MeSH Term	Description	Entries
D007213	Indomethacin	A non-steroidal anti-inflammatory agent (NSAID) that inhibits CYCLOOXYGENASE, which is necessary for the formation of PROSTAGLANDINS and other AUTACOIDS. It also inhibits the motility of POLYMORPHONUCLEAR LEUKOCYTES.	Amuno,Indocid,Indocin,Indomet 140,Indometacin,Indomethacin Hydrochloride,Metindol,Osmosin
D008168	Lung	Either of the pair of organs occupying the cavity of the thorax that effect the aeration of the blood.	Lungs
D004285	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)	Canis familiaris,Dog
D006221	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)	1,1,1-Trifluoro-2-Chloro-2-Bromoethane,Fluothane,Ftorotan,Narcotan
D000818	Animals	Unicellular or multicellular, heterotrophic organisms, that have sensation and the power of voluntary movement. Under the older five kingdom paradigm, Animalia was one of the kingdoms. Under the modern three domain model, Animalia represents one of the many groups in the domain EUKARYOTA.	Animal,Metazoa,Animalia
D000860	Hypoxia	Sub-optimal OXYGEN levels in the ambient air of living organisms.	Anoxia,Oxygen Deficiency,Anoxemia,Deficiency, Oxygen,Hypoxemia,Deficiencies, Oxygen,Oxygen Deficiencies
D014661	Vasoconstriction	The physiological narrowing of BLOOD VESSELS by contraction of the VASCULAR SMOOTH MUSCLE.	Vasoconstrictions
D016861	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.	Cyclo-Oxygenase Inhibitor,Cyclooxygenase Inhibitor,Prostaglandin Endoperoxide Synthase Inhibitor,Prostaglandin Endoperoxide Synthase Inhibitors,Prostaglandin Synthase Inhibitor,Prostaglandin Synthase Inhibitors,Prostaglandin Synthesis Antagonist,Prostaglandin Synthesis Antagonists,Cyclo-Oxygenase Inhibitors,Inhibitors, Cyclo-Oxygenase,Inhibitors, Cyclooxygenase,Inhibitors, Prostaglandin Synthase,Inhibitors, Prostaglandin-Endoperoxide Synthase,Antagonist, Prostaglandin Synthesis,Antagonists, Prostaglandin Synthesis,Cyclo Oxygenase Inhibitor,Cyclo Oxygenase Inhibitors,Inhibitor, Cyclo-Oxygenase,Inhibitor, Cyclooxygenase,Inhibitor, Prostaglandin Synthase,Inhibitors, Cyclo Oxygenase,Inhibitors, Prostaglandin Endoperoxide Synthase,Synthase Inhibitor, Prostaglandin,Synthesis Antagonist, Prostaglandin
D066298	In Vitro Techniques	Methods to study reactions or processes taking place in an artificial environment outside the living organism.	In Vitro Test,In Vitro Testing,In Vitro Tests,In Vitro as Topic,In Vitro,In Vitro Technique,In Vitro Testings,Technique, In Vitro,Techniques, In Vitro,Test, In Vitro,Testing, In Vitro,Testings, In Vitro,Tests, In Vitro,Vitro Testing, In