Effect of luminal calcium on Ca2+ release channel activity of sarcoplasmic reticulum in situ.
Effect of luminal calcium on Ca2+ release channel activity of sarcoplasmic reticulum in situ.
复制标题
管腔钙对原位肌浆网Ca2+释放通道活性的影响。
DOI：
10.1016/s0006-3495(98)77890-7
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发表时间：
1998
影响因子：
3.4
通讯作者：
Y. Ogawa
中科院分区：
文献类型：
--
作者：
N. Kurebayashi;Y. Ogawa
在无Ca 2+泵活性的情况下，在去皮的青蛙骨骼肌纤维中测定Ca 2+流入空SR，并与来自负载SR的Ca 2+流出（即，Ca 2+释放），以加深我们对Ca 2+释放通道（CRC）特性的理解。SR中的钙含量大致呈一级动力学增加，并最终达到由胞浆Ca ~（2+）（[Ca ~（2+）]C）决定的平衡水平。由于AMP引起Ca 2+内流速率增加，普鲁卡因、Mg 2+和高浓度Ca 2+引起特征性降低，因此得出结论，主要的Ca 2+内流途径是CRC，Ca 2+释放也是如此。钙外流的表观速率常数（kapp）没有显着变化时，负荷水平降低到三分之一。在[Ca ~（2+）]C一定的条件下，SR内钙平衡与钙内流和外流的平衡相似。SR中[Ca ~（2+）] C与Ca ~（2+）之间的关系表明SR中存在Ca ~（2+）结合位点，这些结果以及这些Ca ~（2+）缓冲位点对动力学的预期影响与管腔Ca ~（2+）抑制CRC的观点一致。
Ca2+influx into empty SR in the absence of Ca2+pump activity was determined in skinned frog skeletal muscle fibers and compared with Ca2+efflux from loaded SR (i.e., Ca2+release) to deepen our understanding of the properties of the Ca2+release channel (CRC). Calcium content in SR increased approximately in a first-order kinetics and finally reached the equilibrium level determined by cytoplasmic Ca2+([Ca2+]C). Because AMP caused an increase in the rate of Ca2+influx, and procaine, Mg2+, and high concentrations of Ca2+caused a characteristic decrease, the major Ca2+influx pathway was concluded to be the CRC, as is true of Ca2+release. The apparent rate constant (kapp) of Ca2+efflux did not significantly change when the loading level was decreased to one-third. At a given [Ca2+]C, the same equilibrium level of calcium in SR was attained with a similarkappby both Ca2+influx and Ca2+efflux. The relationship between [Ca2+]Cand calcium in SR indicated the Ca2+binding sites in SR. These results, together with the anticipated effects of these Ca2+buffer sites on kinetics, are consistent with the idea that luminal Ca2+inhibits the CRC.
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影响因子：
2.9
作者：
MEISSNER, G;DARLING, E;EVELETH, J
通讯作者：
EVELETH, J
影响因子：
5.5
作者：
BAYLOR, SM;CHANDLER, WK;MARSHALL, MW
通讯作者：
MARSHALL, MW
影响因子：
56.9
作者：
MA, J;FILL, M;CORONADO, R
通讯作者：
CORONADO, R
FK506 结合蛋白介导的骨骼肌兰尼碱受体的校正。
DOI：
10.1016/s0006-3495(95)80109-8
发表时间：
1995
期刊：
Biophysical journal.
影响因子：
--
作者：
Ma,J;Bhat,MB;Zhao,J
通讯作者：
Zhao,J