Endothelin-1 enhances vasoconstrictor responses to exogenously administered and neurogenically released ATP in rabbit isolated perfused arteries.
Vasoconstrictor responses to ATP were enhanced in a concentration-dependent-manner by endothelin-1 (0.1-1 nM) in isolated perfused segments of rabbit ear artery. Higher concentrations of endothelin-1 (3-10 nM) also enhanced vasoconstrictor responses to ATP. The enhancement of ATP responses by endothelin-1 (0.1-10 nM) was not affected by nicardipine (10 nM). The ATP-mediated component of the vasoconstrictor response to perivascular nerve stimulation in the rabbit jejunal artery was enhanced by endothelin-1 to a similar extent as that to exogenously administered ATP. The enhancement of vasoconstrictor responses to neurogenic ATP was also not affected by nicardipine.
La
M
M
Department of Pharmacology, University of Melbourne, Parkville, Victoria, Australia.
Rand
M J
MJ
D000255:Adenosine Triphosphate / Q000494:pharmacology* / Q000502:physiology*; D000818:Animals; D001158:Arteries / Q000187:drug effects; D004431:Ear, External / Q000098:blood supply; D004558:Electric Stimulation; D016232:Endothelins / Q000494:pharmacology*; D005260:Female; D066298:In Vitro Techniques; D007583:Jejunum / Q000098:blood supply; D009131:Muscle, Smooth, Vascular / Q000187:drug effects*; D009529:Nicardipine / Q000494:pharmacology; D011817:Rabbits; D014661:Vasoconstriction / Q000187:drug effects*
D016232:Endothelins; D000255:Adenosine Triphosphate; D009529:Nicardipine