Endothelin-1 increases arterial sensitivity to 5-hydroxytryptamine.

P M Consigny

doi:10.1016/0014-2999(90)90439-d

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Endothelin-1 increases arterial sensitivity to 5-hydroxytryptamine.

P M Consigny

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Abstract

Rings of rabbit abdominal aorta were pretreated with endothelin-1 (ET-1) or vehicle and then isometric contractions to cumulative additions of 5-hydroxytryptamine (5-HT) were recorded. ET-1 at concentrations of 0.4, 1 and 2 nM produced contractions of 7, 15 and 35% of maximal potassium chloride-induced contractions, respectively. Pretreatment of aortic rings with these concentrations of ET-1 increased (P less than 0.01) arterial sensitivity (EC50) to 5-HT 1.9-, 2.4- and 3.5-fold, respectively, without affecting peak 5-HT-induced force. Acetylcholine-induced, endothelium-dependent aortic relaxations were not affected by pretreatment with ET-1-pretreated but not untreated aortic rings. These results suggest that ET-1 could promote arterial vasospasm by sensitizing the artery to 5-HT released from platelets.

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Acetylcholine Animals Aorta, Abdominal Endothelins In Vitro Techniques Isometric Contraction Muscle Contraction Muscle Relaxation Muscle, Smooth, Vascular Potassium Chloride Rabbits Serotonin Swine Journal Article Research Support, Non-U.S. Gov't

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P M Consigny. 1990-09-21. Endothelin-1 increases arterial sensitivity to 5-hydroxytryptamine.. https://doi.org/10.1016/0014-2999(90)90439-d

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