精氨酸血管催产素对两栖动物的心脏影响。

The cardiac effects of arginine vasotocin in amphibians.

Chiu K W, Lim H Y, Pang P K

Department of Biology, Chinese University of Hong Kong, Shatin, N.T.

Comp Biochem Physiol C Comp Pharmacol Toxicol. 1988;89(2):147-51. doi: 10.1016/0742-8413(88)90201-0.

Abstract

The cardiac effects of arginine vasotocin (AVT) on isolated atria were examined in three anuran and one urodele species. 2. AVT produced dose-related positive chronotropic and inotropic responses. 3. The responsiveness of the atrial tissue varied among species. 4. Both the basal atrial rate (AR) and tension (T) were attenuated in the presence of phentolamine and propranolol, alpha- and beta-adrenergic antagonists. Isoproterenol, a beta-adrenergic agonist, increased both AR and T, an effect which would be inhibited by propranolol. 5. The effects of AVT on both AR and T were not inhibited by alpha- and beta-adrenergic blockers, nor by verapamil and imidazole with the dosages used in the present study. 6. On the contrary, the effects of AVT on AR, but not T, was enhanced in the presence of both alpha- and beta-adrenergic blockers. 7. The mechanism of action of AVT on the amphibian atrium remains unknown.

摘要

在三种无尾目动物和一种有尾目动物中研究了精氨酸血管催产素（AVT）对离体心房的心脏效应。2. AVT产生剂量相关的正性变时和变力反应。3. 心房组织的反应性在不同物种间有所差异。4. 在α-和β-肾上腺素能拮抗剂酚妥拉明和普萘洛尔存在的情况下，基础心房率（AR）和张力（T）均降低。β-肾上腺素能激动剂异丙肾上腺素增加了AR和T，普萘洛尔可抑制该效应。5. 本研究中所用剂量的α-和β-肾上腺素能阻滞剂、维拉帕米和咪唑均未抑制AVT对AR和T的作用。6. 相反，在α-和β-肾上腺素能阻滞剂同时存在的情况下，AVT对AR的作用增强，但对T的作用未增强。7. AVT对两栖类心房的作用机制尚不清楚。