Morphological Alteration and the Protein Expression of Caspase -3 in Denervated Posterior Cricoarytenoid Muscles / 听力学及言语疾病杂志

ABSTRACT

Objective To investigate the morphological alteration and the protein expression of caspase -3 in long -term denervated posterior cricoarytenoid muscles (PCAMs)in order to find the appropriate time point of rein‐neration in long -term denervated PCAMs .Methods A total of 45 patients with vocal paralysis were recruited and devided into 3 groups ,the 3~6 months denervation group ,the 6~12 months denervation group ,the 1~2 year denervation group .12 adults served as control group .The morphological alteration was evaluated using HE staining and the change in expression of caspase -3 ,an apoptosis related factor ,were observed using immunehistochemistry stain and western blot .Results With elongation of denervation time ,there were increased denaturation in the mus‐cle fibers .The nucleus moved inside and some of them concentrated .Caspase-3 showed weak staining in innerva‐ted ,however ,by 3-6 months of muscle denervation there was a significant accumulation of caspase -3 protein in myofibers ,6~12 months and 1~2 years of denervation ,expression of caspase -3 protein in myofibers was de‐creased significantly .In western blot ,the change in protein expression of caspase -3 was observed an 21-fold (P< 0 .01) increase from 3~6 months denervated muscles to innervated muscles ,11-fold (P< 0 .01) increase from 6~12 months denervated muscles to innervated muscles ,3~fold (P< 0 .01) increase from 1~2 year denervated muscles to innervated muscles .Conclusion The morphological alterations and changes in expression of caspase -3 indicated there was a high amplitude of apoptosis in denervated posterior cricoarytenoid muscles within 1 year .