Interference of pentobarbital and verapamil with the reactivity of middle cerebral artery of cat exposed to experimental subarachnoid hemorrhage.
1. Pentobarbital and verapamil produced concentration-dependent vasodilation in segments of middle cerebral artery of either control or exposed to experimental subarachnoid hemorrhage (SAH) cats precontracted with 5-hydroxytryptamine (5-HT, 10(-5) M) or K+ (75 mM), the potency to evoke relaxation being greater for verapamil than pentobarbital. 2. Pentobarbital (10(-4) M and 10(-3) M) or verapamil (10(-6) M) inhibited the contractions induced by 10(-5) M 5-HT or 75 mM K+ in both kinds of vessels. 3. Pentobarbital (10(-3) M) and verapamil (10(-6) M) reduced the concentration-dependent contractions induced by Ca2+ addition in control and SAH arteries previously exposed to Ca2+-free medium containing K+ or 5-HT. 4. All these vasodepressor effects of pentobarbital and verapamil were similar in control and SAH vessels, suggesting that the sensitivity of them to these agents is unaffected by SAH.
Marín
J
J
Departamento de Farmacología y Terapéutica y Fisiología, Facultad de Medicina, Universidad Autónoma, Madrid, Spain.
Martinez-Aldama
J
J
Salaices
M
M
D000818:Animals; D002415:Cats; D002536:Cerebral Arteries / Q000187:drug effects* / Q000503:physiopathology; D005260:Female; D008297:Male; D010424:Pentobarbital / Q000494:pharmacology*; D011188:Potassium / Q000494:pharmacology; D013345:Subarachnoid Hemorrhage / Q000503:physiopathology*; D014700:Verapamil / Q000494:pharmacology*
D014700:Verapamil; D010424:Pentobarbital; D011188:Potassium