[Apoptosis and expression of apoptosis-related proteins in experimental different denervated guinea-pig facial muscle].
OBJECTIVE
To study apoptosis and expression of apoptosis-related proteins in experimental different denervated guinea-pig facial muscle.


METHODS
An experimental model was established with guinea pigs by compressing the facial nerve 30 second (reinnervated group) and resecting the facial nerve (denervated group). TUNEL method and immunohistochemical technique (SABC) were applied to detect the apoptosis and expression of apoptosis-related proteins bcl-2 and bax from 1st to 8th week after operation.


RESULTS
Experimentally denervated facial muscle revealed consistently increase of DNA fragmentation, average from(34.4 +/- 4.6)% to (38.2 +/- 10.6)%, from 1st week to 8th week after operation; Reinnervated facial muscle showed a temporal increase of DNA fragmentation, and then the muscle fiber nuclei revealed decreased DNA fragmentation along with the function of facial nerve recovered, latterly normal, average from (32.0 +/- 8.03)% to (5.6 +/- 3.5)%, from 1st week to 8th week after operation. In denervated group, bcl-2 and bax were expressed strongly; in reinnervated group, bcl-2 expressed consistently, but bax disappeared latterly along with the function of facial nerve recovered.


CONCLUSIONS
Expression of DNA fragmentation and apoptosis-related proteins in denervated muscle are general reaction to denervation. bcl-2 can prevent early apoptotic muscle fiber to survival until reinnervation. It is concluded that proteins control apoptosis may give information for possible therapeutic interventions to reduce the rate of muscle fiber death in denervated atrophy in absence of effective primary treatment.
Hui
Lian
L
Department of Otorhinolaryngology, First Affiliated Hospital of China Medical University, Shenyang 110001, China. huilian613@hotmail.com
Wei
Hong-Quan
HQ
Li
Xiao-Tian
XT
Guan
Chao
C
Ren
Zhong
Z
D000818:Animals; D017209:Apoptosis; D003714:Denervation; D005152:Facial Muscles / Q000166:cytology* / Q000294:innervation / Q000378:metabolism*; D005260:Female; D006168:Guinea Pigs; D008297:Male; D019253:Proto-Oncogene Proteins c-bcl-2 / Q000378:metabolism
D019253:Proto-Oncogene Proteins c-bcl-2