坦索罗辛：3H-哌唑嗪与牛前列腺、大鼠心脏和大脑中两种α1-肾上腺素能受体亚型（α1H和α1L）结合亲和力的评估。

Tamsulosin: assessment of affinity of 3H-prazosin bindings to two alpha1-adrenoceptor subtypes (alpha1H and alpha1L) in bovine prostate and rat heart and brain.

Maruyama K, Nakamura T, Yoshihara T, Fukutomi J, Sugiyama K, Hattorim K, Ohnuki T, Watanabe K, Nagatomo T

Department of Pharmacology, Niigata College of Pharmacy, Japan.

Gen Pharmacol. 1998 Oct;31(4):597-600. doi: 10.1016/s0306-3623(98)00048-2.

Abstract

The present study was designed to assess the displacement potencies of tamsulosin to 3H-prazosin bindings in two alpha1-adrenoceptor (AR) subtypes (alpha1H and alpha1L) in bovine prostate, rat heart and brain compared with those of amosulalol, labetalol, ketanserin, clonidine and propranolol. 2. The pKi values of tamsulosin to alpha1H and alpha1L subtypes in bovine prostate were 9.13 and 8.99 and these values were almost the same as those of prazosin. On the other hand, low pKi binding values of amosulalol, labetalol, ketanserin, clonidine and propranolol to these subtypes were observed. 3. Low pKi values of tamsulosin to alpha2- and beta-ARs and muscarinic and 5HT2 receptors in the rat brain were observed. 4. These results suggest that tamsulosin has high affinities to alpha1L-AR subtypes in bovine prostate and rat hearts as well as alpha1H-AR subtypes, implying an inhibitory effect of this drug on the contraction of the prostate.

摘要

本研究旨在评估与阿莫洛尔、拉贝洛尔、酮色林、可乐定和普萘洛尔相比，坦索罗辛对牛前列腺、大鼠心脏和大脑中两种α1肾上腺素能受体（AR）亚型（α1H和α1L）的3H-哌唑嗪结合的置换能力。2. 坦索罗辛对牛前列腺中α1H和α1L亚型的pKi值分别为9.13和8.99，这些值与哌唑嗪的几乎相同。另一方面，观察到阿莫洛尔、拉贝洛尔、酮色林、可乐定和普萘洛尔对这些亚型的低pKi结合值。3. 观察到坦索罗辛对大鼠脑中α2-和β-AR以及毒蕈碱和5HT2受体的低pKi值。4. 这些结果表明，坦索罗辛对牛前列腺和大鼠心脏中的α1L-AR亚型以及α1H-AR亚型具有高亲和力，这意味着该药物对前列腺收缩有抑制作用。