Endothelin induced cerebral vasoconstriction in rainbow trout, detected in a novel in vitro preparation.
We have here developed an in vitro method for examining cerebral vasoconstriction/vasodilation in fish brain tissue, relying on microscopic observation of the diameter of an artery (denoted tectal artery) on the ventral side of the isolated optic tectum of rainbow trout (Oncorhynchus mykiss). Using this technique, we show that endothelin-1 (ET-1) is a powerful vasoconstrictor in rainbow trout brain. When surperfused over the optic tectum, 1.0-2.5 nM of ET-1 caused 23 and 46% reductions, respectively, in the tectal artery diameter. This vasoconstriction could be completely blocked by the endothelin receptor antagonist bosentan. ET-1 is the first substance shown to constrict cerebral arteries in fish.
Paslawski Rødland
Terese
T
Division of General Physiology, Department of Biology, University of Oslo, P.O. Box 1051, 0316 Oslo, Norway.
Nilsson
Göran E
GE
D000818:Animals; D002560:Cerebrovascular Circulation / Q000187:drug effects*; D004305:Dose-Response Relationship, Drug; D016232:Endothelins / Q000494:pharmacology*; D066298:In Vitro Techniques; D017686:Oncorhynchus mykiss; D013997:Time Factors; D014661:Vasoconstriction / Q000187:drug effects*
D016232:Endothelins