Stimulation of protein synthesis and glucose utilization in the hypoglossal nucleus induced by axotomy
Stimulation of protein synthesis and glucose utilization in the hypoglossal nucleus induced by axotomy
复制标题
轴索切断术诱导舌下核蛋白质合成和葡萄糖利用的刺激
作者：
C. Smith;A. Crane;M. Kadekaro;B. Agranoff;L. Sokoloff
本文研究了单侧切断第12脑神经后大鼠舌下神经核的代谢反应。用两种定量放射自显影技术，L-[1- 14 C]亮氨酸法和[14 C]脱氧葡萄糖法，分别测定再生核中蛋白质合成和葡萄糖利用率的变化。结果表明，与假手术动物相比，这两个过程在同侧神经核中增加，而在对侧神经核中不受影响。这些代谢变化的时间进程进行了比较的功能神经支配的舌头的回报。葡萄糖利用率的增加首先在切开术后24小时检测到。它是最大的1和3天之间的postaxotomy和构成了一个84%的增长率在对侧控制核。蛋白质合成的增加幅度小于葡萄糖利用的增加幅度。它是最大的轴突切断后48小时，并构成了一个25%的增长率在对侧核。这两种代谢过程的增加甚至在舌功能恢复后21天仍然存在。蛋白质合成和葡萄糖利用率在术后24 - 35天恢复到正常水平。虽然蛋白质合成和葡萄糖利用率的变化的时间过程是相似的，葡萄糖利用率的增加幅度太大，不能用蛋白质合成相对较小的增加所需的能量来解释，并且可能也反映了其他过程，包括再生神经元的胞体-树突膜的功能改变。
The metabolic responses of rat hypoglossal nuclei to unilateral section of the 12th cranial nerve have been studied. Changes in the rates of protein synthesis and glucose utilization in the regenerating nucleus were determined with two quantitative autoradiographic techniques, the L-[1–14C]leucine method and the [14C] deoxyglucose method, respectively. The results show that both of these processes increase in the nucleus ipsilateral to the sectioned nerve and are unaffected in the contralateral nucleus as compared with sham-operated animals. The time courses of these metabolic changes have been compared with that of the return of functional innervation of the tongue. An increase in glucose utilization is first detected 24 hr postaxotomy. It is maximal between 1 and 3 days postaxotomy and constitutes an 84% increase over the rate in the contralateral control nucleus. The increase in protein synthesis is of smaller magnitude than that of glucose utilization. It is maximal at 48 hr after axotomy and constitutes a 25% increase over the rate in the contralateral nucleus. The increases in both of these metabolic processes persist even after functional recovery of the tongue at 21 days postaxotomy. Protein synthesis and glucose utilization return to normal levels between 24 and 35 days postaxotomy. Although the time courses of the changes in protein synthesis and glucose utilization are similar, the magnitude of the increase in glucose utilization is too large to be accounted for by the energy requirements of the relatively small increase in protein synthesis and probably reflects other processes as well, including altered function of the soma-dendritic membrane of regenerating neurons.