Interaction of BKCa channel modulators with adrenergic agonists in the rat aorta is influenced by receptor reserve

被引：3

作者：

El-Hajj, H ^{[1
]}

Chandrasekhar, B ^{[1
]}

Kadavil, EA ^{[1
]}

Oriowo, MA ^{[1
]}

机构：

[1] Kuwait Univ, Fac Med, Dept Pharmacol & Toxicol, Safat 13110, Kuwait

来源：

VASCULAR PHARMACOLOGY | 2004年 / 41卷 / 4-5期

关键词：

noradrenaline; tetraethylammonium; phenoxybenzamine;

D O I：

10.1016/j.vph.2004.10.001

中图分类号：

R9 [药学];

学科分类号：

1007 ;

摘要：

Our main objective was to study the interaction of BKCa channel modulators with adrenergic agonists UK 14304 and noradrenatine (NA), acting on alpha(1)-adrenoceptors, in the rat aorta and how this is affected by receptor reserve. NA and UK 14304 evoked concentration-dependent contractions of the rat aorta. UK 14304 was a partial agonist relative to NA in this preparation. The BKCa channel blocker tetraethylammonium (TEA, 1 mM) and opener NS 1619 (3 x 10(-5) M) modulated NA- and UK 14304-induced contractions, and were more effective on UK 14304-induced contractions. TEA (1 mM) increased the maximum response to NA and UK 14304 by about 13% and 300%, respectively, while NS 1619 (3 x 10-5 M) reduced the maximum response to UK 14304 by about 81% compared to 31% for noradrenaline. The effect of TEA on the noradrenaline concentration-response curve was increased after treatment of the aorta with phenoxybenzamine (PBZ), an irreversible alpha(1)-adrenoceptor antagonist, to reduce receptor reserve. We concluded that the interaction of BKCa channel modulators with alpha(1)-adrenergic agonists in the rat aorta was influenced by receptor reserve. (C) 2004 Elsevier Inc. All rights reserved.

引用

页码：119 / 124

页数：6