莫能菌素对血管平滑肌培养物中钠钾泵的可逆性刺激作用。

Reversible stimulation of the Na+/K+ pump by monensin in cultures of vascular smooth muscle.

作者信息

Brock T A, Smith J B

出版信息

Life Sci. 1982 Sep 6;31(10):1043-50. doi: 10.1016/0024-3205(82)90177-1.

Abstract

Two ionophores, monensin and salinomycin, increased total cell Na+ and ouabain-sensitive 86Rb+ uptake in cultures of smooth muscle cells from rat aorta. Monensin was used to produce graded increases in cell Na+ in order to assess the Na+ dependence of the Na+/K+ pump in the intact cell. The relationship between internal Na+ and ouabain-sensitive 86Rb+ uptake was hyperbolic (K'Na = 3 mM). Monensin did not stimulate 86Rb+ uptake in the absence of external Na+. Loading the cells with Na+ by exposing cultures to a K+-free medium for 3 hr maximally increased cell Na+ and ouabain-sensitive 86Rb+ uptake to the same extent as monensin. Total cell Na+ and pump activity in monensin-treated cells returned to the initial values after removing the ionophore. Monensin was then able to increase total cell Na+ and ouabain-sensitive 86Rb+ uptake to the same extent as the initial treatment with the ionophore.

摘要

两种离子载体，莫能菌素和盐霉素，可增加大鼠主动脉平滑肌细胞培养物中细胞总钠含量以及哇巴因敏感的⁸⁶Rb⁺摄取量。使用莫能菌素使细胞内钠含量逐步增加，以评估完整细胞中钠钾泵对钠的依赖性。细胞内钠含量与哇巴因敏感的⁸⁶Rb⁺摄取量之间的关系呈双曲线关系（K'Na = 3 mM）。在无细胞外钠的情况下，莫能菌素不会刺激⁸⁶Rb⁺摄取。通过将培养物置于无钾培养基中3小时使细胞加载钠，可使细胞总钠含量和哇巴因敏感的⁸⁶Rb⁺摄取量达到与莫能菌素处理相同的最大增加程度。去除离子载体后，莫能菌素处理细胞中的细胞总钠含量和泵活性恢复到初始值。随后，莫能菌素能够使细胞总钠含量和哇巴因敏感的⁸⁶Rb⁺摄取量增加到与最初使用离子载体处理时相同的程度。