对大鼠两种不同功能运动神经元群调质CGRP配布式样研究

Studies on Distribution Patterns of Modulator CGRP in Different Motoneuron Pools in Rats

应用霍乱毒素Ｂ亚单位结合胶体金（ＣＢ－Ａｕ）逆行标认复合降钙素基因相关肽样免疫细胞化学反应（ＣＧＲＰ－ＬＩ）的方法，对发育过程中大鼠比目鱼肌（慢肌）和趾长伸肌（快肌）运动神经元群的ＣＧＲＰ－ＬＩ含量强度配布式样进行了分析。结果表明，大鼠快、慢肌运动神经元群之间的ＣＧＲＰ－ＬＩ含量强度在发育过程中即有着明显的不同，慢肌运动神经元群中含有较多ＣＧＲＰ－ＬＩ阴性和弱阳性运动神经元，而快肌运动神经元群含较多ＣＧＲＰ－ＬＩ强阳性的运动神经元，表明调质ＣＧＲＰ与运动神经元群所支配的肌肉功能活动方式密切相关。

Using retrograde labelling combined with calcitonin gene-related peptide(CGRP) immunocytochemistry technique,distribution patterns of the content of calcitonin gene-related peptide-like immunoreactivity(CGRP-LI) were studied in two different motoneuron(Mn) pools supplying soleus(SOL,slow-twitch muscle) and extensor digitorium longus (EDL,fast-twitch muscle) of hindlimbs in rats during development.The Mn pools were identified with a novel retrograde tracer,choleragen B subunit(CB)coupled with colloidal gold(CBAu,5 nm particle,prepared by ourselves),which was injected into EDL or SOL,After the silver intensification for visualizing colloidal gold particles,CGRP immunocytochemistry were processed.The CB-Au retrogradely identified Mns in each Mn pool were counted and CGRP-LI intensity of Mns was evaluated as strong,moderate,weak and negative,The double labelling revealed different distribution patterns of CGRP-LI content between SOL and EDL Mn pools during development.Comparing the level of CGRP expression between the two Mn pools,SOL Mn pool had a higher ratio of neurons lacking CGRP-LI/weak CGRP LI and a lower proportion of strongly CGRP-LI labelled ones,These results suggest that the difference in content of CGRP-LI in Mns is related to the type of muscular motor activity.