OBJECTIVETo investigate the activity of bilateral posterior cricoarytenoid muscle satellite cell after denervation or reinnervation with ansa cervicalis.

METHODSTwenty 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.

RESULTSTwo 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.

CONCLUSIONSThe 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.