Role of creatine kinase in force development in chemically skinned rat cardiac muscle
Role of creatine kinase in force development in chemically skinned rat cardiac muscle
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肌酸激酶在化学剥皮大鼠心肌力量发展中的作用
DOI：
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发表时间：
1987
期刊：
影响因子：
--
通讯作者：
G. Vassort
中科院分区：
文献类型：
--
作者：
R. Ventura;H. Mekhfi;G. Vassort
本文研究了磷酸肌酸对Triton X-100处理的大鼠心肌细乳头肌和心室条中有无镁三磷酸腺苷和镁腺苷的影响。分析了PCA/张力关系、pMgATP/张力关系以及张力对长度快速变化的响应。结果表明，在存在毫摩尔浓度的镁三磷酸腺苷的情况下，磷酸肌酸浓度降低的三个主要后果。(A)静息张力和最大钙激活张力增加，PCA/张力关系向更高的PCA值移动，其陡度降低，这些作用被加入镁ADP增强。(B)在最大激活时施加快速拉伸后，张力恢复的时间常数增加，而恢复的幅度减小。(C)低钙条件下pMgATP/张力关系的研究表明，磷酸肌酸的减少导致最大僵直张力和斜率系数不变，但向更高的镁ATP值转变；这些影响随着镁ADP的增加而增加，并且与制剂的直径无关。因此，当磷酸肌酸减少时，表观钙敏感性、静息和最大张力的改变似乎是由于僵直或缓慢骑行的跨桥参与增加，花费更多的时间在附着状态。这些结果表明，内源性肌酸激酶能够通过产生局部高的镁ATP/镁ADP比率来确保肌球蛋白ATPase的最大效率。
The influence of phosphocreatine in the presence or absence of MgATP and MgADP was studied in Triton X-100-treated thin papillary muscles and ventricular strips of the rat heart. The pCa/tension relationships, the pMgATP/tension relationships, and the tension responses to quick length changes were analyzed. The results show three major consequences of the reduction of the phosphocreatine concentration in the presence of millimolar concentrations of the MgATP. (a) The resting tension and the maximal Ca2+-activated tension were increased, and the pCa/tension relationship was shifted toward higher pCa values and its steepness was decreased; these effects were enhanced by the inclusion of MgADP. (b) The time constant of tension recoveries after quick stretches applied during maximal activation was increased, while the extent of these recoveries was decreased. (c) The study of pMgATP/tension relationships in low Ca concentrations showed that the decrease in phosphocreatine induced a shift toward higher MgATP values with no changes in maximal rigor tension or the slope coefficient; these effects were increased by the increase in MgADP and were independent of the preparation diameter. Thus, modifications of the apparent Ca sensitivity and resting and maximal tension when phosphocreatine is decreased seem to be due to an increasing participation of rigor-like or slowly cycling cross-bridges spending more time in the attached state. These results suggest that endogenous creatine kinase is able to ensure maximal efficiency of myosin ATPase by producing a local high MgATP/MgADP ratio.
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通过心肌细胞中的磷酸肌酸穿梭从线粒体到肌原纤维的能量传输。
DOI：
10.1152/ajpcell.1983.245.5.c423
发表时间：
1983
期刊：
The American journal of physiology
影响因子：
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作者：
McClellan,G;Weisberg,A;Winegrad,S
通讯作者：
Winegrad,S
DOI：
10.1016/s0021-9258(19)70187-2
发表时间：
1980-12
期刊：
The Journal of biological chemistry
影响因子：
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作者：
M. Holroyde;S. P. Robertson;J. Johnson;R. Solaro;J. D. Potter
通讯作者：
M. Holroyde;S. P. Robertson;J. Johnson;R. Solaro;J. D. Potter
细胞内 pH 在控制正常和缺血心肌收缩力中的作用：31P 核磁共振和质谱研究。
DOI：
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发表时间：
1981
期刊：
Kroc Foundation series
影响因子：
--
作者：
Jacobus,WE;Pores,IH;Lucas,SK;Kallman,CH;Weisfeldt,ML;Flaherty,JT
通讯作者：
Flaherty,JT
DOI：
10.1073/pnas.77.8.4717
发表时间：
1980-01-01
期刊：
PROCEEDINGS OF THE NATIONAL ACADEMY OF SCIENCES OF THE UNITED STATES OF AMERICA-BIOLOGICAL SCIENCES
影响因子：
--
作者：
BRANDT, PW;COX, RN;KAWAI, M
通讯作者：
KAWAI, M