SIGNALING IN CARDIAC MYOCYTES-LOCAL WARMING

摘要

Although the concept of local calcium signaling in cardiac muscle has been extensively characterized since its initial mathematical description and experimental observation, recent studies have revealed new insights on this topic. This local warming is nicely summarized in the Viewpoint by Fowler and Smith. A crucial aspect of local calcium signaling is the physical apposition of two membranes, from the sarcolemma and sarcoplasmic reticulum, which forms a restricted diffusion space, therefore allowing local spatial concentration gradients to occur. In ventricular myocytes from mammals, this junctional cleft is present at the surface membrane and the t-tubules, with no experimental evidence suggesting differences in the dyad structure at the two sites.