Responses of contractile properties in rat soleus to high-energy phosphates and/or unloading.
Responses of contractile properties in rat soleus to high-energy phosphates and/or unloading.
复制标题
大鼠比目鱼肌收缩特性对高能磷酸盐和/或卸载的反应。
DOI：
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发表时间：
1994
期刊：
影响因子：
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通讯作者：
M. Yamamoto
中科院分区：
文献类型：
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作者：
T. Wakatsuki;Y. Ohira;W. Yasui;K. Nakamura;T. Asakura;H. Ohno;M. Yamamoto
在大鼠中研究了比目鱼肌收缩特性对卸载和/或高能磷酸盐含量变化的反应。通过喂食β-胍基丙酸（β-GPA）可诱导踝伸肌中高能磷酸盐（尤其是磷酸肌酸）的减少。该研究的主要发现是，疲劳性和与速度相关的收缩特性以类似的方式对卸载和肌酸补充做出反应。补充肌酸和后肢悬液10天后高能磷酸盐含量有升高趋势。在喂食 β-GPA 的大鼠中观察到向慢速型的转变，主要是由于二分之一松弛时间的增加。通过喂食肌酸或悬吊后肢可以逆转这种转变。然而，β-GPA 喂养并不能完全阻止悬浮引起的收缩特性向快速型的转变。虽然单独喂食β-GPA 不会改变肌肉疲劳抵抗力，但在β-GPA 组中，暂停和肌酸供给后疲劳抵抗力的下降较小。研究表明，高能磷酸盐水平和张力产生在比目鱼肌收缩特性的调节中发挥着重要作用。
Responses of contractile properties of soleus to unloading and/or changes in high-energy phosphate contents were studied in rats. Reduction of high-energy phosphates, especially phosphocreatine, in ankle extensors was induced by feeding beta-guanidinopropionic acid (beta-GPA). The major finding in the study was that the fatigability and speed-related contractile properties responded to unloading and creatine supplementation in a similar manner. The high-energy phosphate contents tended to be elevated after 10-d supplementation of creatine and hindlimb suspension. The shift toward slow-type, mainly due to an increased one-half relaxation time, was seen in rats fed beta-GPA. Such a shift was reversed by feeding creatine or by hindlimb suspension; however, the suspension-induced shift of contractile properties toward fast-type was not prevented completely by beta-GPA feeding. Although the muscle fatigue resistance did not change by beta-GPA feeding alone, the decrease in fatigue resistance following suspension and creatine supply was less in the beta-GPA group. It is suggested that the levels of high-energy phosphates and tension production play important roles in the regulation of contractile properties of the soleus muscle.