Effects of catalase and endothelin on anoxia-induced vasoconstriction of porcine basilar artery in vitro.
OBJECTIVE
To study whether anoxia-induced vasoconstriction was related to the release of endothelin (ET).


METHODS
Acute anoxia was induced by gassing the organ chamber with 95% N2 + 5% CO2. Changes in tension of porcine basilar arterial ring was recorded.


RESULTS
Anoxia-induced increases in tension were 0.21 g +/- 0.08 g and 0.24 g +/- 0.09 g under basal tension and during ET 3 nmol.L-1-induced contractions, respectively. In the rings tension did not further augment following the increase of ET from 100 to 300 nmol.L-1, acute anoxia did cause further increase in tension of 0.16 g +/- 0.10 g (n = 4). Catalase 800 and 2400 kU.L-1 decreased the anoxia-induced contraction, with inhibitory rate of 33% +/- 7% and 47% +/- 9%, respectively.


CONCLUSIONS
Anoxia-induced vasoconstriction was related to release of hydrogen peroxide from endothelial cells.
Gong
Q Y
QY
Department of Pharmacology, Basic Medical College, Shanghai Medical University, China. mhyao@shmu.edu.cn
Luo
G Q
GQ
D000818:Animals; D001488:Basilar Artery / Q000187:drug effects*; D002374:Catalase / Q000494:pharmacology*; D015687:Cell Hypoxia; D016232:Endothelins / Q000037:antagonists & inhibitors*; D004730:Endothelium, Vascular / Q000378:metabolism; D066298:In Vitro Techniques; D013552:Swine; D014661:Vasoconstriction / Q000187:drug effects*
D016232:Endothelins; D002374:Catalase