Endothelin receptor mediating contraction of isolated bovine coronary artery

Citation
S. Ishiguro et al., Endothelin receptor mediating contraction of isolated bovine coronary artery, J VET PHARM, 24(3), 2001, pp. 203-208
Citations number
32
Language
INGLESE
art.tipo
Article
Categorie Soggetti
Veterinary Medicine/Animal Health
Journal title
JOURNAL OF VETERINARY PHARMACOLOGY AND THERAPEUTICS
ISSN journal
0140-7783 → ACNP
Volume
24
Issue
3
Year of publication
2001
Pages
203 - 208
Database
ISI
SICI code
0140-7783(200106)24:3<203:ERMCOI>2.0.ZU;2-R
Abstract
We studied endothelin (ET) receptors and their subtypes on isolated bovine coronary arteries. Endothelin receptors that mediated contraction of isolat ed bovine coronary artery were characterized by the use of antagonists and agonists. Contractions induced by the nonselective agonist ET-1 (10(-10)-10 (-7) M) were not affected by the removal of the endothelium (pEC(50): 8.52, maximal contraction: 105% of that induced by 60 mM KCl), BQ-123 (3 x 10(-7 ) M) antagonized contractions of endothelium-denuded coronary rings induced by low concentrations of ET-1 (10(-10) or 10(-9) M), but potentiated the c ontractions induced by higher concentrations of ET-1 (3 x 10(-8) and 10(-7) M). BQ-788 (10(-6) M) potentiated contractions induced by ET-1 (3 x 10(-10 ) and 10(-7) M), In the presence of BQ-788 (10(-6) M), BQ-123 (3 x 10(-8)-3 x 10(-6) M) concentration - dependently inhibited contractions induced by ET-1 (3 x 10(-10) and 10(-7) M) (pA(2): 6.61), Sarafotoxin S6b (10(-9)-3 x 10(-7) M) evoked contractions in the denuded coronary artery (pEC(50): 8.49 , maximal contraction: 139% of 60 mM KCI), The BQ-123 caused a concentratio n-dependent rightward shift of contractions induced by sarafotoxin S6b (pA( 2): 7.89). The present study indicates that ET-1 and sarafotoxin S6b contra ct the isolated bovine coronary artery by stimulating ETA receptors on smoo th muscle cells, and that ETB receptors might suppress the ET-1-induced con tractions.