摘要目的 探讨家犬双侧环杓后肌失神经支配及用颈袢神经再吻合支配后肌卫星细胞活性的变化.方法 随机数字表法将24只家犬分成3组,每组8只,分别为切断双侧喉返神经组,切断喉返神经后即刻颈袢神经再吻合组,不切断喉返神经的对照组.3组动物手术后再饲养9周后再次暴露喉返神经及环杓后肌,使用喉返神经诱发环杓后肌电位来验证喉返神经的再通情况;双盲法提取环杓后肌肌肉组织中总RNA,反转录后做实时定量聚合酶链反应(PCR)检测肌卫星细胞增殖分化标记物Myogenin、Myf5和Pax7的mRNA表达.结果 手术后3组动物各有1只死亡或感染退出实验.术后9周诱发神经环杓后肌肌电图提示对照组动物喉返神经功能均正常,切断组7只动物电刺激都没有反应,吻合组均有神经再通.Myogenin的mRNA相对表达量切断组较对照组和吻合组均有明显升高(Z值为1.42和1.38,P值均＜0.05),Myf5的mRNA表达切断组也明显高于对照组和吻合组(Z值为1.66和1.69,P值均＜0.01);切断组Pax7的mRNA表达明显高于对照组(Z=1.66,P＜0.01),也高于吻合组(Z=1.42,P＜0.05);而吻合组与对照组Myogenin、Myf5和Pax7的mRNA表达差异均无统计学意义(P值均＞0.05).结论 双侧喉返神经切断后,环杓后肌的肌卫星细胞增殖分化的mRNA表达增强,而同颈袢神经再吻合后肌卫星细胞的增殖分化表达下降.

abstractsObjective To investigate the activity of bilateral posterior cricoarytenoid muscle satellite cell after denervation or reinnervation with ansa cervicalis. Methods Twenty four dogs were randomly divided into 3 groups. The bilateral laryngeal recurrent nerves were cut in group one in all dogs. The bilateral laryngeal recurrent nerves were anastomosed with ansa cervicalis after incision in group two in all dogs. The dogs in group three were used as control. Nine weeks after surgery, the electromyography was used to test the regeneration of the nerve. The posterior cricoarytenoid muscles biopsy were collected. The expression of mRNA of Myogenin, Myf5, and Pax7 was assayed by realtime RT-PCR after total RNA isolation. Results Two dogs died after surgery in incision and anastomose group. The electromyography suggested that the RLN of all dogs had denervated in the incision group and had reinnervated in the anastomose group after 9 weeks. Myogenin mRNA from RLN incision dogs PCA muscles had greater expression versus controls ( Z = 1.42, P ＜ 0. 01 ) or anastomosed dogs ( Z = 1.38, P ＜ 0. 01 ). Myf5 mRNA expression from RLN incision dogs PCA muscles had significant increase versus control dogs ( Z = 1.66, P ＜0. 01 ) or anastomosed dogs ( Z = 1.69, P ＜ 0. 01 ). Pax7 mRNA expression from RNL incision dogs had significant increase compared with control ( Z = 1.66, P ＜0. 01 ) or anastomosed animals ( Z = 1.42, P ＜0. 05 ). There was no significant difference in Myogenin ( Z = 1.34, P ＞ 0. 05 ), Myf5 ( Z = 0. 54, P ＞0. 05) and Pax ( Z = 0. 54, P ＞ 0. 05 ) mRNA expression between controls and anastomosed animals.Conclusions The bilateral denervation of RLN cause significantly increasing in dog PCA muscle satellite cell proliferation and differentiation. The bilateral reinnervation of RLN cause PCA muscle satellite cell come back nonproliferative, quiescent state in dog.