A Morphological Study on the Changes in Rat's Gastrocnemius

쥐의 비복근 섬유의 변화에 대한 형태학적 연구

Twelve Spraque-Dawley healthy male rats(average weight ; 250g)were used to study the morphological changes of mitochondria, myofibril, muscle cell nucleus, triad. They were devided into 3 groups : normal daily activity (Group 1), 2weeks immobilization (Group 2), 4 weeks immobilization(Group 3). Left ankle of Group 2 and 3 were immobilized with plaster cast in $65^{\circ}$ plantarflexed position. The gastrocnemius were removed from 12 rats. Muscle fibers were observed electronmicroscopically by double staining with uranyl acetate and lead citrate, All the variables of Group 2 and 3 that selected in this study were significantly decreased when decreased with control value (p<.05) but also muscle fibers showed extensive damage, characterized by irregularity of mitochondrias and wide separation of myofibrils. irregularity and thinness of myofilaments and abnormal shape of muscle cell nucleus and unclear triad. Especially, sarcomere length of Group 3 were singnificantly decreased when compared with Group 2(p<.01).

본 연구는 실험용 려 12마리를 정상관, 2주 고정군, 4주 고정군에 각각 4마리씩 배정하고 석고 고정 기간 후 비복근의 절편을 취하여 투과전자현미경으로 형태학적 관찰을 한 결과를 다음과 같이 요약할 수 있다. 골격근을 짧은 위치로 일정 기간 고정하면 근절의 길이와 폭은 물론 삼조체, 글리코겐, 필라멘트 단백질, 미토콘드리아와 근 세포 핵의 모양까지도 심한 변화가 일어나기 때문에 구축과 위축의 개념에 근원 섬유의 조직, 형태학적 의의를 추가하여야 할 것으로 사료된다.