Effect of removal of the endothelium on vasocontraction in canine and rabbit basilar arteries.
The effect of endothelium removal on the contractile responses to KCl, hemoglobin, serotonin (5-HT), norepinephrine (NE), prostaglandin (PG)F2 alpha, PGD2, and PGE2 was investigated in canine and rabbit basilar arteries by an isometric tension-recording method. In canine basilar arteries, endothelium removal elevated the dose-response curves to 5-HT, PGF2 alpha, and PGD2, and PGE2, but not to KCl, hemoglobin, or NE. In rabbit basilar arteries, on the other hand, removal of the endothelium elevated the dose-response curves to 5-HT, NE, PGF2 alpha, and PGD2, but not to KCl or hemoglobin. Neither contractile nor inhibitory response was elicited by PGE2 in rabbit basilar arteries. Contraction induced by 5-HT and NE following endothelium removal had a much more pronounced effect in rabbit basilar arteries than in canine basilar arteries. These results suggest that, following endothelium removal, abolition of the spontaneous release of endothelium-derived relaxing factor is the most probable mechanism of the enhanced vasocontraction. Since endothelial damage results from subarachnoid hemorrhage, the aforementioned mechanism of vasocontraction enhancement may play a role in the pathogenesis of cerebral vasospasm.
D000818:Animals; D001488:Basilar Artery / Q000187:drug effects / Q000502:physiology*; D001688:Biological Products / Q000378:metabolism; D015237:Dinoprost; D015232:Dinoprostone; D004285:Dogs / Q000502:physiology; D004305:Dose-Response Relationship, Drug; D004727:Endothelium / Q000502:physiology*; D005260:Female; D006454:Hemoglobins / Q000494:pharmacology; D008297:Male; D018377:Neurotransmitter Agents / Q000494:pharmacology*; D009569:Nitric Oxide; D009638:Norepinephrine / Q000494:pharmacology; D011189:Potassium Chloride / Q000494:pharmacology; D015230:Prostaglandin D2; D011453:Prostaglandins / Q000494:pharmacology*; D011457:Prostaglandins D / Q000494:pharmacology; D011458:Prostaglandins E / Q000494:pharmacology; D011460:Prostaglandins F / Q000494:pharmacology; D011817:Rabbits / Q000502:physiology; D012701:Serotonin / Q000494:pharmacology; D013045:Species Specificity; D014661:Vasoconstriction / Q000187:drug effects*; D014665:Vasodilator Agents / Q000378:metabolism
D001688:Biological Products; D006454:Hemoglobins; D018377:Neurotransmitter Agents; D011453:Prostaglandins; D011457:Prostaglandins D; D011458:Prostaglandins E; D011460:Prostaglandins F; D014665:Vasodilator Agents; D009569:Nitric Oxide; D012701:Serotonin; D011189:Potassium Chloride; D015237:Dinoprost; D015232:Dinoprostone; D015230:Prostaglandin D2; D009638:Norepinephrine