Effect of ryanodine on calcium in cardiac muscle.
نویسندگان
چکیده
NAYLER, WINIFRED G., P. DAILE, DENISE CHIPPERFIELD, AND AND K. GAN. E&t of ryanodine on calcium in cardiac muscle. Am. j. Physiol. 219(6): 1620-1626. 1970.-The negative inotropic effect of ryanodine on mammalian heart muscle is accompanied by highly significant changes in time taken during contraction for peak tension to develop. Relaxation is slowed. Influx of 45ca remains unchanged and 4Qa efflux is significantly enhanced. The 45Ca accumulating activity of cardiac sarcotubules is diminished and the activity of the Ca ++-dependent (but not of the basic ATPase enzyme) increases, indicating that ryanodine uncouples ATP hydrolysis and Ca++ uptake. The Ca++-binding capacity of troponin is not changed.
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عنوان ژورنال:
- The American journal of physiology
دوره 219 6 شماره
صفحات -
تاریخ انتشار 1970