Gene/Protein Disease Symptom Drug Enzyme Compound
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Query: UMLS:C0003129 (Anoxia)
 551 document(s) hit in 31,850,051 MEDLINE articles (0.00 seconds)

Experiments were designed to determine the role of the endothelial cells and the metabolism of arachidonic acid in anoxic contractions of isolated canine basilar arteries. Rings, with and without endothelium, of these arteries were suspended for isometric tension recording; anoxia was induced by switching the mixture gassing the organ chamber from 95% O2-5% CO2 to 95% N2-5% CO2. In rings with endothelium, anoxia evoked increases in tension under basal conditions and during contractions to 5-hydroxytryptamine, uridine triphosphate, prostaglandin F2 alpha, and high K+. Under control conditions, these anoxic contractions were not prevented by alpha-adrenergic and serotonergic antagonists, by apyrase, or by inhibitors of cyclooxygenase. Anoxia prevented endothelium-dependent relaxations evoked by vasopressin and thrombin. In rings without endothelium, anoxia caused increases in tension during contractions evoked by various agonists, and in unstimulated preparations after inhibition of cyclooxygenase. Anoxic contractions were abolished by calcium entry blockers. These observations suggest that anoxic contractions of isolated canine basilar artery can be explained by the release of endothelium-derived contracting factor(s) and the accelerated entry of calcium in the smooth muscle cells, which possibly results from a diversion of arachidonic acid from the cyclooxygenase to the lipoxygenase pathway.
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PMID:Anoxic contractions in isolated canine cerebral arteries: contribution of endothelium-derived factors, metabolites of arachidonic acid, and calcium entry. 243 36

Endothelium-dependent contractions of isolated veins can be induced with arachidonic acid and thrombin. Anoxia causes endothelium-dependent contractions in a variety of isolated arteries and veins. Rapid stretch and acetylcholine contract cerebral arteries with, but not those without endothelium. Acetylcholine (and serotonin) cause endothelium-dependent contractions in the aorta of the spontaneously hypertensive, but not that of the normotensive rat.
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PMID:Endothelium-dependent contractions in arteries and veins. 310 28

Experiments were designed to determine the role of the endothelium in the responsiveness of the arterial wall to anoxia. Paired rings of canine femoral arteries were mounted for isometric tension recording in organ chambers filled with aerated Krebs-Ringer bicarbonate solution (37 degrees C). One ring served as control; in the other the intimal layer was removed mechanically. Anoxia was induced by gassing the organ chamber with 95% N2/5% CO2. In control rings anoxia augmented contractile responses to noradrenaline, KCl and BaCl2. On return to O2 the contractile responses were transiently depressed. Removal of the endothelium reduced the anoxic augmentation, but did not affect the post-anoxic inhibition. Indomethacin did not affect the response to anoxia. Anoxia abolished the endothelium-dependent inhibitory effect of acetylcholine and thrombin, reduced that of adenosine triphosphate, but augmented that of arachidonic acid. These experiments indicate that endothelial cells may contribute to anoxic facilitation of the responsiveness of the canine arterial wall.
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PMID:Anoxia and endothelium-dependent reactivity of the canine femoral artery. 687 96