Yogo K, Yano S, Watanabe K
Department of Drug Evaluation and Toxicological Sciences, Faculty of Pharmaceutical Sciences, Chiba University, Japan.
Jpn J Pharmacol. 1990 Jan;52(1):160-3. doi: 10.1254/jjp.52.160.
In the isolated rat stomach perfused with Krebs-Henseleit solution at 36 degrees C, endothelin induced vasoconstriction in a dose-dependent manner. The threshold dose for inducing vasoconstriction was very small, and the pressor response to a bolus injection at 0.1 nmol lasted more than 1 hr. In contrast, the vasoconstrictor effects of noradrenaline and serotonin were transient. The magnitude of the maximal response to endothelin was almost the same as that to noradrenaline, but greater than that to serotonin. The pressor response to serotonin, but not noradrenaline, was greatly augmented after pretreatment with endothelin. These results suggest that endothelin causes a long-lasting vasoconstriction, which would be associated with its ulcerogenic activity, especially in combination with other vasoactive agents under some pathophysiological conditions.
在36℃用克雷布斯 - 亨泽莱特溶液灌注的离体大鼠胃中，内皮素以剂量依赖的方式诱导血管收缩。诱导血管收缩的阈剂量非常小，0.1纳摩尔的单次注射引起的升压反应持续超过1小时。相比之下，去甲肾上腺素和血清素的血管收缩作用是短暂的。内皮素最大反应的幅度与去甲肾上腺素几乎相同，但大于血清素。用内皮素预处理后，血清素（而非去甲肾上腺素）引起的升压反应大大增强。这些结果表明，内皮素引起持久的血管收缩，这可能与其致溃疡活性有关，特别是在某些病理生理条件下与其他血管活性药物联合时。
