期刊
BRITISH JOURNAL OF PHARMACOLOGY
卷 160, 期 1, 页码 160-170出版社
WILEY
DOI: 10.1111/j.1476-5381.2010.00687.x
关键词
oestrogen; endocrine disruptor; large conductance Ca2+; voltage-sensitive potassium channel; KCNMA1; KCNMB1; K(Ca)1; 1; penitrem A
资金
- West Virginia University
Background and purpose: Bisphenol A (BPA) is used to manufacture plastics, including containers for food into which it may leach. High levels of exposure to this oestrogenic endocrine disruptor are associated with diabetes and heart disease. Oestrogen and oestrogen receptor modulators increase the activity of large conductance Ca2+/voltage-sensitive K+ (Maxi-K; K(Ca)1.1) channels, but the effects of BPA on Maxi-K channels are unknown. We tested the hypothesis that BPA activates Maxi-K channels through a mechanism that depends upon the regulatory beta 1 subunit. Experimental approach: Patch-clamp recordings of Maxi-K channels were made in human and canine coronary smooth muscle cells as well as in AD-293 cells expressing pore-forming alpha or alpha plus beta 1 subunits. Key results: BPA (10 mu M) activated an outward current in smooth muscle cells that was inhibited by penitrem A (1 mu M), a Maxi-K blocker. BPA increased Maxi-K activity in inside-out patches from coronary smooth muscle, but had no effect on single channel conductance. In AD-293 cells with Maxi-K channels composed of alpha subunits alone, 10 mu M BPA did not affect channel activity. When channels in AD-293 cells contained beta 1 subunits, 10 mu M BPA increased channel activity. Effects of BPA were rapid (< 1 min) and reversible. A higher concentration of BPA (100 mu M) increased Maxi-K current independent of the beta 1 subunit. Conclusions and implications: Our data indicate that BPA increased the activity of Maxi-K channels and may represent a basis for some potential toxicological effects.
作者
我是这篇论文的作者
点击您的名字以认领此论文并将其添加到您的个人资料中。
推荐
暂无数据