Chalmers Susan, Olson Marnie L, MacMillan Debbi, Rainbow Richard D, McCarron John G
Division of Physiology and Pharmacology, Strathclyde Institute of Pharmacy and Biomedical Sciences, University of Strathclyde, 27 Taylor Street, Glasgow G4 0NR, UK.
Cell Calcium. 2007 Oct-Nov;42(4-5):447-66. doi: 10.1016/j.ceca.2007.05.010. Epub 2007 Jul 13.
In smooth muscle, Ca(2+) regulates cell division, growth and cell death as well as providing the main trigger for contraction. Ion channels provide the major access route to elevate the cytoplasmic Ca(2+) concentration (Ca(2+)) in smooth muscle by permitting Ca(2+) entry across the plasma membrane and release of the ion from intracellular Ca(2+) stores. The control of Ca(2+) relies on feedback modulation of the entry and release channels by Ca(2+) itself. Local rises in Ca(2+) may promote or inhibit channel activity directly or indirectly. The latter may arise from Ca(2+) regulation of ionic conductances in the plasma membrane to provide control of cell excitability and so Ca(2+) entry. Organelles such as mitochondria may also contribute significantly to the feedback regulation of ion channel activity by the control of Ca(2+) or redox status of the cell. This brief review describes the feedback regulation of Ca(2+) release from the internal Ca(2+) store and of plasma membrane excitability in smooth muscle.
在平滑肌中，Ca(2+) 调节细胞分裂、生长和细胞死亡，同时也是引发收缩的主要因素。离子通道是平滑肌中提高细胞质 Ca(2+) 浓度（[Ca(2+)]c）的主要途径，它允许 Ca(2+) 通过质膜进入细胞，并从细胞内 Ca(2+) 储存库中释放离子。[Ca(2+)]c 的调控依赖于 Ca(2+) 自身对进入和释放通道的反馈调节。[Ca(2+)]c 的局部升高可能直接或间接促进或抑制通道活性。后者可能源于 Ca(2+) 对质膜离子电导的调节，从而控制细胞兴奋性以及 [Ca(2+)]c 的进入。线粒体等细胞器也可能通过控制细胞的 Ca(2+) 或氧化还原状态，对离子通道活性的反馈调节起到重要作用。本简要综述描述了平滑肌中细胞内 Ca(2+) 储存库释放 Ca(2+) 的反馈调节以及质膜兴奋性的反馈调节。
