Tyc F, Vrbová G
Department of Anatomy and Developmental Biology, UCL, London, UK.
Brain Res Dev Brain Res. 1995 Sep 29;88(2):186-93. doi: 10.1016/0165-3806(95)00096-v.
The effect on inhibiting the calcium activated neutral protease (CANP) by leupeptin on force output and motor unit size of the partially denervated rat EDL muscle was studied. Partial denervation was performed under anaesthesia by section of the L4 ventral ramus in 3- and 18-day-old Wistar rats. Two days after the operation a silicon strip containing the inhibitor of CANP leupeptin was implanted alongside the partially denervated EDL. Two to 3 months later the animals were anaesthetized and the EDL muscles on both sides prepared for tension recording. The results from these recordings show dramatic reduction in force output and muscle weight in animals operated at 3 days and this reduction was less pronounced in muscles treated with leupeptin. The mean force output of individual motor units increases in the leupeptin-treated partially denervated muscle compared to the untreated muscle. The increased fatigue resistance typical of muscles partially denervated at 3 days [37] is less pronounced in the treated muscle. In animals operated at 18 days the individual motor units actually increased in size and the leupeptin treatment had no effect on the partially denervated EDL muscles. The difference between the response to leupeptin of the 3 day and 18 day operated animals could be due to the different patterns of innervation of the muscles at the time of the application of the inhibitor of CANP.
研究了亮抑蛋白酶肽对部分失神经支配的大鼠趾长伸肌（EDL）肌肉力量输出和运动单位大小的钙激活中性蛋白酶（CANP）抑制作用。在麻醉下，对3日龄和18日龄的Wistar大鼠切断L4腹支进行部分去神经支配。术后两天，将含有CANP抑制剂亮抑蛋白酶肽的硅条植入部分失神经支配的EDL旁边。两到三个月后，对动物进行麻醉，并准备好双侧EDL肌肉用于张力记录。这些记录结果显示，3日龄手术动物的力量输出和肌肉重量显著降低，而用亮抑蛋白酶肽处理的肌肉中这种降低不太明显。与未处理的肌肉相比，在亮抑蛋白酶肽处理的部分失神经支配肌肉中，单个运动单位的平均力量输出增加。3日龄部分失神经支配肌肉典型的增加的抗疲劳能力在处理过的肌肉中不太明显。在18日龄手术的动物中，单个运动单位实际上增大了，亮抑蛋白酶肽处理对部分失神经支配的EDL肌肉没有影响。3日龄和18日龄手术动物对亮抑蛋白酶肽反应的差异可能是由于在应用CANP抑制剂时肌肉的不同神经支配模式。
