Watson J E, Gordon T, Jones R, Smith M E
Pflugers Arch. 1976 May 12;363(2):161-6. doi: 10.1007/BF01062285.
Preincubation of normal rat soleus muscles in vitro with homogenates prepared from mixed leg muscles which had been denervated 4 days previously resulted in an increase in the contracture response to acetylcholine. After 30 min incubation a 1.5-fold increase was observed. Homogenates of normally innervated muscles did not increase the response. The active principles of the denervated muscles were found to reside in the "cytosol" fraction. An approximately 2-fold increase was observed upon incubation with the cytosol for 30 min; incubation for longer periods resulted in a subsequent decrease in the response. The effect of the denervated muscle cytosol was concentration-dependent and heat-labile. Normal muscle cytosol also increased the soleus muscle response to acetylcholine but this fraction was less effective than denervated muscle cytosol. The response of control muscles incubated in Krebs-Henseleit solution was found to decrease with time. Commercially obtained phospholipases C and D increased the response of normal soleus muscles approximatley 2-fold. Phospholipase A, lipase, trypsin, collagenase and a bacterial protease had no effect, lysozyme produced a small but consistent increase in the response to acetylcholine.
将4天前已去神经支配的混合腿部肌肉制备的匀浆与正常大鼠比目鱼肌在体外进行预孵育，结果导致比目鱼肌对乙酰胆碱的挛缩反应增强。孵育30分钟后，观察到反应增加了1.5倍。正常神经支配肌肉的匀浆并未增加该反应。发现去神经支配肌肉的活性成分存在于“胞质溶胶”部分。与胞质溶胶孵育30分钟后，观察到反应增加了约2倍；孵育更长时间会导致反应随后下降。去神经支配肌肉胞质溶胶的作用具有浓度依赖性且对热不稳定。正常肌肉胞质溶胶也增加了比目鱼肌对乙酰胆碱的反应，但该部分的效果不如去神经支配肌肉胞质溶胶。发现在Krebs-Henseleit溶液中孵育的对照肌肉的反应随时间而降低。市售的磷脂酶C和D使正常比目鱼肌的反应增加了约2倍。磷脂酶A、脂肪酶、胰蛋白酶、胶原酶和一种细菌蛋白酶没有作用，溶菌酶使对乙酰胆碱的反应产生了小而持续的增加。
