米诺地尔的α2-肾上腺素能受体激动剂活性的证据。

Evidence for alpha 2-adrenoceptor agonist activity of minoxidil.

作者信息

Sharma N, Mehta A A, Santani D D, Goyal R K

机构信息

Department of Pharmacology, L. M. College of Pharmacy, Ahmedabad, India.

出版信息

J Pharm Pharmacol. 1997 Sep;49(9):935-7. doi: 10.1111/j.2042-7158.1997.tb06139.x.

DOI:10.1111/j.2042-7158.1997.tb06139.x

PMID:9306265

Abstract

The present investigation was undertaken to study the mechanism of action of minoxidil using various smooth muscle preparations. Minoxidil (4.7 x 10(-6) M to 4.7 x 10(-4) M) produced a concentration-dependent inhibition of field stimulation-evoked responses in rat anococcygeus muscle and vas deferens. The inhibition produced by minoxidil was antagonized by yohimbine (2.5 x 10(-7) M). Minoxidil (1.4 x 10(-5) M to 4.7 x 10(-4) M) also produced a concentration-dependent relaxation in oestrogen-primed potassium chloride-depolarized rat uterus. These responses were blocked not only by yohimbine but also by glibenclamide (2.02 x 10(-8) M). Our results suggest that minoxidil possesses alpha 2-adrenoceptor agonist activity in addition to potassium-channel-opening activity.

摘要

本研究旨在利用各种平滑肌制剂研究米诺地尔的作用机制。米诺地尔（4.7×10⁻⁶M至4.7×10⁻⁴M）对大鼠肛门尾骨肌和输精管的场刺激诱发反应产生浓度依赖性抑制。米诺地尔产生的抑制作用可被育亨宾（2.5×10⁻⁷M）拮抗。米诺地尔（1.4×10⁻⁵M至4.7×10⁻⁴M）对雌激素预处理的氯化钾去极化大鼠子宫也产生浓度依赖性松弛作用。这些反应不仅被育亨宾阻断，还被格列本脲（2.02×10⁻⁸M）阻断。我们的结果表明，米诺地尔除具有开放钾通道活性外，还具有α₂ -肾上腺素能受体激动剂活性。