Kawamura M, Inagami T
Endocrinology. 1983 May;112(5):1857-9. doi: 10.1210/endo-112-5-1857.
Effects of calmodulin antagonists on renin release from isolated rat glomeruli were examined. The calmodulin antagonists used were N-(6-aminohexyl)-5-chloro-naphthalene-1-sulfonamide (W-7), triflupromazine and trifluoperazine. These drugs induced renin release from isolated glomeruli in a dose-dependent manner. The threshold concentration for renin release in the calcium-containing medium was 50 microM for W-7, 5 microM for triflupromazine and 2 microM for trifluoperazine respectively. The threshold concentrations were 2-5 times less in the calcium-free medium. The maximum levels of renin release by the three antagonists were similar in both calcium-containing and calcium-free media. In the absence of these antagonists, the basal rate of renin release in the calcium-free medium was markedly higher than in the calcium-containing medium. These results suggest that the calcium-calmodulin system inhibits renin release and that renin release is regulated by a mechanism different from the calcium-stimulated exocytotic mechanism by which many hormones are released.
研究了钙调蛋白拮抗剂对离体大鼠肾小球肾素释放的影响。所用的钙调蛋白拮抗剂为N-(6-氨基己基)-5-氯萘-1-磺酰胺（W-7）、三氟拉嗪和三氟哌嗪。这些药物以剂量依赖的方式诱导离体肾小球释放肾素。在含钙培养基中，W-7、三氟拉嗪和三氟哌嗪引起肾素释放的阈值浓度分别为50微摩尔、5微摩尔和2微摩尔。在无钙培养基中，阈值浓度低2至5倍。三种拮抗剂在含钙和无钙培养基中引起的肾素释放最大水平相似。在没有这些拮抗剂的情况下，无钙培养基中肾素释放的基础速率明显高于含钙培养基。这些结果表明，钙-钙调蛋白系统抑制肾素释放，且肾素释放受一种不同于许多激素释放所依赖的钙刺激胞吐机制的调节机制调控。
