Gill Donald L, Patterson Randen L
Department of Biochemistry and Molecular Biology, University of Maryland School of Medicine, Baltimore, MD 21201, USA.
Sci STKE. 2004 Jul 20;2004(243):pe39. doi: 10.1126/stke.2432004pe39.
Receptor-induced Ca2+ signals involve both Ca2+ release from intracellular stores and extracellular Ca2+ entry across the plasma membrane. The channels mediating Ca2+ entry and the mechanisms controlling their function remain largely a mystery. Here we critically assess current views on the Ca2+ entry process and consider certain modifications to the widely held hypothesis that Ca2+ store emptying is the fundamental trigger for receptor-induced Ca2+ entry channels. Under physiological conditions, receptor-induced store depletion may be quite limited. A number of distinct channel activities appear to mediate receptor-induced Ca2+ entry, and their activation is observed to occur through quite diverse coupling processes.
受体诱导的Ca2+信号涉及细胞内钙库释放Ca2+以及细胞外Ca2+通过质膜进入细胞。介导Ca2+进入的通道及其功能调控机制在很大程度上仍是个谜。在此，我们批判性地评估了当前关于Ca2+进入过程的观点，并对广泛持有的假说进行了某些修正，该假说认为钙库排空是受体诱导的Ca2+进入通道的基本触发因素。在生理条件下，受体诱导的钙库耗竭可能相当有限。一些不同的通道活性似乎介导了受体诱导的Ca2+进入，并且观察到它们的激活是通过相当多样的偶联过程发生的。
