Adreani C M, Kaufman M P
Division of Cardiovascular Medicine, Departments of Internal Medicine and Human Physiology, University of California, Davis, California 95616, USA.
J Appl Physiol (1985). 1998 Jun;84(6):1827-33. doi: 10.1152/jappl.1998.84.6.1827.
Our laboratory has shown previously that a low level of dynamic exercise induced by electrical stimulation of the mesencephalic locomotor region (MLR) stimulated group III and IV muscle afferents in decerebrate unanesthetized cats (C. M. Adreani, J. M. Hill, and M. P. Kaufman. J. Appl. Physiol. 83: 1811-1817, 1997). In the present study, we have extended these findings by examining the effect of occluding the arterial supply to the dynamically exercising muscles on the afferents' responses to MLR stimulation. In decerebrate cats, we found that arterial occlusion increased the responsiveness to a low level of dynamic exercise in 44% of the group III and 47% of the group IV afferents tested. Occlusion, compared with the freely perfused state, did not increase the concentrations of either hydrogen ion or lactate ion in the venous effluent from the exercising muscles. We conclude that arterial occlusion caused some unspecified substance to accumulate in the working muscles to increase the sensitivity of equal percentages of group III and IV afferents to dynamic exercise.
我们实验室先前已表明，在去大脑未麻醉的猫中，通过电刺激中脑运动区（MLR）诱发的低水平动态运动刺激了Ⅲ类和Ⅳ类肌肉传入神经（C.M.阿德雷亚尼、J.M.希尔和M.P.考夫曼。《应用生理学杂志》83: 1811 - 1817, 1997）。在本研究中，我们通过检查阻断动态运动肌肉的动脉供应对传入神经对MLR刺激的反应的影响，扩展了这些发现。在去大脑的猫中，我们发现动脉阻断使44%的Ⅲ类和47%的受试Ⅳ类传入神经对低水平动态运动的反应性增加。与自由灌注状态相比，阻断并未增加运动肌肉静脉流出液中氢离子或乳酸离子的浓度。我们得出结论，动脉阻断导致某种未明确的物质在工作肌肉中积累，从而使相同比例的Ⅲ类和Ⅳ类传入神经对动态运动的敏感性增加。
