Static muscular contraction elicits a pressor reflex in the chicken.
Static muscular contraction elicits a pressor reflex in the chicken.
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静态肌肉收缩引起鸡的升压反射。
DOI：
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发表时间：
1997
影响因子：
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通讯作者：
T. Adamson
中科院分区：
文献类型：
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作者：
I. Solomon;T. Adamson
在人类和其他哺乳动物中，静态肌肉收缩已被证明可以增加动脉血压和心率。然而，目前还不清楚鸟类是否对这种动作表现出类似的反应。因此，我们设计了这些实验，以确定鸡是否对静态肌肉收缩表现出心血管反应，以及观察到的反应是否通过涉及肌肉传入的反射来诱发。在13只氯醛糖麻醉公鸡上，以1.5~3.0倍的运动阈值(30~40 Hz，0.025 ms)电刺激坐骨神经，诱发腓肠肌的静态收缩。我们测量了静态收缩前和收缩期间的动脉血压和肌张力，并根据动脉压轨迹计算平均动脉压和心率。我们发现，腓肠肌的静态收缩使平均动脉压从71+/-4毫米汞柱增加到95+/-4毫米汞柱(P<；0.05)，心率从304+/-8次/分增加到345+/-10次/分(P<；0.05)。此外，我们发现，用维库溴铵刺激鸟类瘫痪后的坐骨神经或刺激坐骨神经切断的外周末端(使用上述相同的刺激参数)不会引起平均动脉压或心率的变化。我们得出结论，鸡腓肠肌的静态肌肉收缩引起升压反应，这种反应是由收缩肌肉产生的反射引起的。
Static muscular contraction has been shown to increase arterial blood pressure and heart rate in humans and other mammals. It is not clear, however, whether birds exhibit a similar response to this maneuver. Therefore, we designed these experiments to determine if the chicken exhibits a cardiovascular response to static muscular contraction and if the observed responses are evoked through a reflex involving muscle afferents. Static contraction of the gastrocnemius muscle was evoked by electrically stimulating the sciatic nerve at 1.5-3.0 times motor threshold (30-40 Hz; 0.025 ms) in 13 chloralose-anesthetized cockerels. We measured arterial blood pressure and muscle tension before and during static contraction and calculated mean arterial pressure and heart rate from the arterial pressure trace. We found that static contraction of the gastrocnemius muscle increased mean arterial pressure from 71 +/- 4 to 95 +/- 4 mmHg (P < 0.05) and increased heart rate from 304 +/- 8 to 345 +/- 10 beats/min (P < 0.05). Furthermore, we found that stimulation of the sciatic nerve after paralysis of the birds with vecuronium bromide or stimulation of the cut peripheral end of the sciatic nerve (using the same stimulation parameters described above) evoked no change in mean arterial pressure or heart rate. We conclude that static muscular contraction of the gastrocnemius muscle in the chicken elicits a pressor response and that this response is due to a reflex arising from the contracting muscles.