5-羟色胺和去甲肾上腺素对大鼠肛门尾骨肌作用的比较研究。

Comparative studies of the effects of 5-hydroxytryptamine and noradrenaline on the rat anococcygeus muscle.

作者信息

Goyal R K, Patel N M, Verma S C

出版信息

Agents Actions. 1981 Dec;11(6-7):677-72. doi: 10.1007/BF01978787.

DOI:10.1007/BF01978787

Abstract

The effects of 5-hydroxytryptamine (5HT) and noradrenaline (NA) have been studied on rat anococcygeus muscle. 1. 5HT and NA produced a dose-dependent contraction of rat anococcygeus muscle. Cyproheptadine (1.0 X 10(-6) M), a specific 5HT receptor blocker, failed to inhibit the responses to either 5HT or NA. 2. However, phentolamine, a specific alpha receptor antagonist competitively blocked the responses to 5HT and NA. 3. The responses to 5HT were inhibited in the reserpinized (5 mg/kg i.p. 24 h) and 6-hydroxydopamine (6-OHDA) pre-treated preparations. 6-OHDA produced a leftward shift of the dose-response curve of NA. Reserpine pre-treatment potentiated lower doses of NA and the threshold dose of NA was significantly decreased. 4. Nialamide (2.2 x 10(-6) M), the mono-amine oxidase inhibitor produced a significant leftward shift of the dose-response curve of both 5HT and NA. Pyrogallol (2.3 x 10(-5) M), the catechol-o-methyl transferase inhibitor also potentiated the responses to both 5HT and NA, but the potentiation was significant at lower doses of 5HT and NA. 5. Our data suggest that 5HT- and NA-induced contractions in rat anococcygeus muscle are mediated through common alpha adrenoceptors. 5HT actions are probably indirect, mediated through the release of NA.

摘要

已对5-羟色胺（5HT）和去甲肾上腺素（NA）对大鼠肛门尾骨肌的作用进行了研究。1. 5HT和NA可使大鼠肛门尾骨肌产生剂量依赖性收缩。赛庚啶（1.0×10⁻⁶ M），一种特异性5HT受体阻滞剂，未能抑制对5HT或NA的反应。2. 然而，酚妥拉明，一种特异性α受体拮抗剂，竞争性地阻断了对5HT和NA的反应。3. 在利血平化（腹腔注射5 mg/kg，24小时）和6-羟基多巴胺（6-OHDA）预处理的制剂中，对5HT的反应受到抑制。6-OHDA使NA的剂量-反应曲线向左移动。利血平预处理增强了较低剂量的NA，且NA的阈剂量显著降低。4. 单胺氧化酶抑制剂尼亚酰胺（2.2×10⁻⁶ M）使5HT和NA的剂量-反应曲线均显著向左移动。儿茶酚-O-甲基转移酶抑制剂焦性没食子酸（2.3×10⁻⁵ M）也增强了对5HT和NA的反应，但在较低剂量的5HT和NA时增强作用显著。5. 我们的数据表明，5HT和NA诱导的大鼠肛门尾骨肌收缩是通过共同的α肾上腺素能受体介导的。5HT的作用可能是间接的，通过NA的释放介导。