SUGAWARA Yasushi Instructor, Dept, of Plastic Surgery, Univ, of Tokyo, 医学部(病), 助手 (60260494)
YOSHIMURA Kotaro Instructor, Dept, of Plastic Surgery, Univ, of Tokyo, 医学部(病), 助手 (60210762)
|Budget Amount *help
¥7,200,000 (Direct Cost : ¥7,200,000)
Fiscal Year 1995 : ¥1,600,000 (Direct Cost : ¥1,600,000)
Fiscal Year 1994 : ¥5,600,000 (Direct Cost : ¥5,600,000)
Denervation models and self-reinnervation models were created with the soleus (SOL) and extensor digitrum longus (EDL) muscles in the hindimb of female wistar rats. Those muscles were removed at 4,8,12, and 24 weeks postoperatively. Myosin isoform composition of themuscle tissue was biochemically analyzed using an pyrophosphate acrylamide gel electrophoresis. The bands weer fainter in denervated muscles than in normal muscles, even though undiluted samples were applied, wihch suggests that there was a decrease in the amount of myosin. In denervated SOL,slow myosin (SM) became sbsent and fast myosin (FM) appeared dominant at 4,8, and 12 postoperative weeks. In denervated EDL,no remarkable changes were seen in electrophoresis pattern other than a faster isoform which is possibly embryonic or neonatal myosin isoform. In the self-reinnervation models, SM,and FM were respectively dominant in the SOL and EDL muscles at all stages, similar to normal muscles. During reinnervation, there was a temporary increase in SM isoform percentages in both muscles, with SOL demonstrating statistically significant differences in the 4th, 8th and 12th, postoperative weeks and EDL in the 12th, postoperative week in comparison with preoperative values. In the 24 th week, when reinnervation had been completed, the SM percentage was significantly increased in SOL and decreased in EDL.The temporary increase in SM isoforms during reinnervation not only experimentally but also clinically.