胰岛素不会通过哇巴因可抑制的过程使大鼠肌肉超极化。

Insulin does not hyperpolarize rat muscle by means of a ouabain-inhibitable process.

作者信息

Zierler K, Rogus E

出版信息

Am J Physiol. 1981 Sep;241(3):C145-9. doi: 10.1152/ajpcell.1981.241.3.C145.

DOI:10.1152/ajpcell.1981.241.3.C145

Abstract

Experiments were designed to test the hypothesis that insulin-induced hyperpolarization of rat skeletal muscle is mediated by stimulation of a ouabain-inhibitable electrogenic pump. Parallel experiments were carried out on rat caudofemoralis with isoproterenol, known to hyperpolarize rat skeletal muscle by stimulation of such a pump. Ouabain (10(-5) M) completely inhibited isoproterenol-induced hyperpolarization within 15 min but had no effect on half-maximal insulin-induced hyperpolarization. Ouabain (10(-6) M) inhibited isoproterenol effect by 60% during a period of 5-15 min. Ouabain (10(-4) M) had no effect on insulin-induced hyperpolarization within 10 min but depolarized during the next 10 min. In a separate series of studies in rat extensor digitorum longus muscle, 10(-5) M ouabain increased intracellular Na+ within 14 min. It is concluded that in rat caudofemoralis muscle, insulin-induced hyperpolarization is not mediated by a ouabain-inhibitable electrogenic pump.

摘要

设计实验以检验如下假说

胰岛素诱导的大鼠骨骼肌超极化是由哇巴因抑制性生电泵的刺激介导的。在大鼠尾股肌上用异丙肾上腺素进行了平行实验，已知异丙肾上腺素通过刺激这种泵使大鼠骨骼肌超极化。哇巴因（10⁻⁵ M）在15分钟内完全抑制了异丙肾上腺素诱导的超极化，但对半数最大胰岛素诱导的超极化没有影响。哇巴因（10⁻⁶ M）在5至15分钟内将异丙肾上腺素的作用抑制了60%。哇巴因（10⁻⁴ M）在10分钟内对胰岛素诱导的超极化没有影响，但在接下来的10分钟内使膜电位去极化。在另一系列对大鼠趾长伸肌的研究中，10⁻⁵ M哇巴因在14分钟内使细胞内钠离子增加。得出的结论是，在大鼠尾股肌中，胰岛素诱导的超极化不是由哇巴因抑制性生电泵介导的。