Phosphocreatine and oxidative metabolism-contraction coupling in rabbit aorta.
Phosphocreatine and oxidative metabolism-contraction coupling in rabbit aorta.
复制标题
兔主动脉中磷酸肌酸和氧化代谢-收缩耦合。
DOI：
10.1152/ajpheart.1989.257.2.h597
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发表时间：
1989
期刊：
影响因子：
--
通讯作者：
Coburn,RF
中科院分区：
文献类型：
--
作者：
Scott,DP;Coburn,RF
通过测量磷酸肌酸 (PCr) 和 ATP 含量的变化、PCr 与游离肌酸 (Cr) 的比率以及细胞能量产生受到抑制的条件下肌肉力量的变化，研究了单个兔主动脉环的氧化代谢-收缩耦合。我们通过使用负载肌酸的环、对照（未负载）环和暴露于零葡萄糖溶液 30 分钟的环来比较总 PCr 含量显着不同的环。肌酸负载导致 PCr 含量增加至对照的 300%。缺氧、0.05 和 0.1 mM 氰化物、从沐浴介质中去除葡萄糖或去除葡萄糖加缺氧会降低 30 µM 去甲肾上腺素产生的维持肌肉力量。在这些扰动的机械效应方面，加载肌酸和未加载肌酸的环之间没有差异。使用与 PCr/Cr 变化相关的各种扰动抑制能量产生而引起的肌肉力量变化。数据与氧化代谢-收缩耦合是通过向控制肌肉力量的反应或反应的能量传递来调节的一致。代谢-收缩耦合不受总能量储存或 PCr 或 Cr 浓度控制。
Oxidative metabolism-contraction coupling was studied in single rabbit aortic rings by measuring changes in phosphocreatine (PCr) and ATP content, the ratio of PCr to free creatine (Cr), and changes in muscle force under conditions in which cellular energy production was inhibited. We compared rings with markedly different total PCr content by using rings loaded with creatine, control (unloaded) rings, and rings exposed for 30 min to zero-glucose solution. Creatine loading resulted in increases in PCr content to 300% of control. Maintained muscle force generated by 30 microM norepinephrine was decreased by hypoxia, 0.05 and 0.1 mM cyanide, removal of glucose from the bathing media, or glucose removal plus hypoxia. There was no difference between creatine-loaded and unloaded rings in the mechanical effects of these perturbations. Changes in muscle force induced by inhibition of energy production using the various perturbations correlated with changes in PCr/Cr. Data are consistent with oxidative metabolism-contraction coupling being regulated by energy delivery to a reaction or reactions controlling muscle force. Metabolism-contraction coupling is not controlled by total energy stores or by PCr or Cr concentration.