Gauthier C, Soustre H
Laboratoire de Physiologie Générale, CNRS 290, Université de Poitiers, France.
Eur J Pharmacol. 1992 Feb 13;225(2):129-35. doi: 10.1016/0922-4106(92)90092-a.
The effects of forskolin, which is known as a direct activator of adenylate cyclase were studied on the slow inward calcium current (Isi) and phasic tension of frog atrial fibres. Forskolin induced a dose-dependent positive inotropic effect related to an increase in the slow inward calcium current. These effects, which were not reproduced by 1,9-dideoxyforskolin, seemed to result from an activation of adenylate cyclase. The action of forskolin was antagonized by adenosine and potentiated by phosphodiesterase inhibitors with the following order of potency: rolipram greater than theophylline greater than dipyridamole; M & B 22,948 was without influence. This study suggests that adenosine and rolipram might be suitable tools for studying the implication of cAMP in the modulation of contraction in frog atrium.
研究了已知为腺苷酸环化酶直接激活剂的福斯高林对青蛙心房纤维慢内向钙电流（Isi）和相位张力的影响。福斯高林诱导出与慢内向钙电流增加相关的剂量依赖性正性肌力作用。这些作用不能被1,9 - 二脱氧福斯高林重现，似乎是由腺苷酸环化酶的激活导致的。福斯高林的作用被腺苷拮抗，被磷酸二酯酶抑制剂增强，其效力顺序如下：咯利普兰大于茶碱大于双嘧达莫；M&B 22,948无影响。本研究表明，腺苷和咯利普兰可能是研究环磷酸腺苷（cAMP）在青蛙心房收缩调节中的作用的合适工具。
