中文摘要：

本研究目的是观察下颌神经切断术后降钙素基因相关肽（CGRP）在大鼠三叉神经运动核（Vmo）内表达的变化.采用免疫组织化学和双重免疫荧光组织化学标记技术,观察了下颌神经切断术后3、7、14、21、28、35和42 d时Vmo内CGRP和胶质纤维酸性蛋白（GFAP）免疫阳性物质表达的变化,并采用图像分析法计数了Vmo内存活的CGRP阳性运动神经元的数量.结果显示：神经切断能够引起手术侧Vmo内CGRP样免疫阳性物质的表达在术后3天和35天时呈＂驼峰式＂上调,且对照侧也有显著变化;定量分析显示神经切断后手术侧Vmo内运动神经元的数量几乎没有明显减少,但运动神经元周围GFAP的表达却大量增加.以上结果提示：Vmo内CGRP表达的上调可能对受损运动神经元的急性应激反应和恢复均具有营养作用,且激活的星形胶质细胞可能参与了其过程.

英文摘要：

The purpose of this study was to investigate the changes of calcitonin gene-related peptide （CGRP） expression in the trigeminal motor nucleus （Vmo） following mandibular nerve transection. The expression of CGRP and glial fibrillary acidic protein （GFAP） were detected at 3, 7, 14, 21, 28, 35 and 42 days post-axotomy （dpa） by using immunohistochemical and double-immunofluorescence histochemical methods. And the number of CGRP-positive surviving motoneurons was examined by using image analysis system. The present results showed that there was a ＂biphasic＂ up-regulation of CGRP-immunoreactivity at 3 and 35 dpa on the ipsilateral side of the Vmo, and significant changes were also observed on the contralateral side. Quantitative analysis revealed that there was almost no loss of motoneurons in the Vmo but there was an evident increase in GFAP expression around the Vmo neurons on the ipsilateral side after axotomy. The present results suggest that the up-regulation of CGRP may exert its trophic effects in both the acute stress reaction and the recovery of the injured motoneurons, and the activated astrocytes may be well involved in this process.