Blood flow in normal and denervated muscle during exercise in conscious rats.
Blood flow in normal and denervated muscle during exercise in conscious rats.
复制标题
清醒大鼠运动期间正常和去神经肌肉的血流量。
DOI：
10.1152/ajpheart.1988.255.6.h1509
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发表时间：
1988
期刊：
影响因子：
--
通讯作者：
Armstrong,RB
中科院分区：
文献类型：
--
作者：
Delp,MD;Armstrong,RB
本研究的目的是检验外部机械因素，即，在肢体运动过程中施加于肌肉上的动态缩短和延长以及随着周围肌肉收缩和放松而产生的有节奏的压缩导致了清醒的雄性Sprague-Dawley大鼠在运动过程中的初始肌肉充血。在运动前几小时，在一条后肢中手术切除比目鱼肌和腓肠肌外侧头的神经，以去除1）局部代谢性血管扩张效应，2）通过交感节后纤维介导的血管收缩或血管扩张效应，以及3）内在机械泵送。在运动前和运动30 s和5 min时，用放射性微球测量大鼠以15 m/min或电动跑步机行走时的血流量。还测量糖原浓度作为肌肉活动的指标以验证去神经支配。正常肢体控制肌肉的血流量与先前报道的运动前和运动期间的值相似。然而，去神经支配减少了运动前主要由氧化纤维组成的肌肉的血流量（69-88%），增加了主要由糖酵解纤维组成的肌肉的血流量（53%）。在运动过程中，流向失神经肌肉的血液要么保持不变，要么减少。这些数据表明，外在的机械因素并没有显着有助于在正常肌肉的低强度运动开始时的初始充血反应。
The purpose of this study was to test the hypothesis that extrinsic mechanical factors, i.e., the dynamic shortening and lengthening imposed on a muscle during limb movements and the rhythmic compressions as surrounding muscles contract and relax, contribute to the initial muscle hyperemia during locomotion in conscious male Sprague-Dawley rats. Soleus and lateral head of gastrocnemius muscles were surgically denervated in one hindlimb several hours before exercise to remove 1) local metabolic vasodilator effects, 2) vasoconstrictor or vasodilatory influences mediated through sympathetic postganglionic fibers, and 3) intrinsic mechanical pumping. Blood flow was measured with radioactive microspheres during preexercise and at 30 s and 5 min of exercise in rats walking at 15 m/min or a motor-driven treadmill. Glycogen concentrations were also measured as an indicator of muscular activity to verify the denervation. Blood flows to control muscles in the normal limb were similar to previously reported values during preexercise and exercise. Denervation, however, decreased preexercise blood flow (69–88%) to muscle composed predominantly of oxidative fibers and increased flow (53%) to muscle composed predominantly of glycolytic fibers. During exercise, blood flow to denervated muscles either remained unchanged or decreased. These data suggest that extrinsic mechanical factors do not significantly contribute to the initial hyperemic response at the onset of low-intensity exercise in normal muscle.