Abstract des Autors

We studied the characteristics of skeletal muscle cardiolipin (CL) with a lapse in muscular atrophy in rats induced by Achilles tendon tenotomy. In an anesthetized state under diethyl ether, the left Achilles tendon was cut off and thereafter, the rats were fed with water and solid food for 3 weeks. In the postabsorptive state, the rat was anesthetized with diethyl ether and the intact gastrocnemius muscles were isolated from both legs. Muscle lipid was separated by thin-layer chromatography and CL fatty acids were analyzed and determined by gas-chromatography. The control muscle weight (right gastrocnemius muscle) increased in proportion to body weight, but the tenotomized muscle weight (left gastrocnemius muscle) remained unchanged up to the 12th day. However, thereafter, the muscle weight sharply recovered to the control level. There was a significant relationship between muscle weight and the linoleic acid composition of the CL in the control muscle (r=0.78, p<0.05). However, in the tenotomized muscle up to the 12th day after tenotomy, the relationship was weak (r=0.43, p<0.05) and thereafter, the relationship became significant (r=0.79, p<0.05). In comparison with the control group, the tenotomized muscle CL from the operation to the 12th day was significantly lower with high linoleic acid composition (p<0.05). Significant relationships between muscle CL and linoleic acid composition were observed in the control (r=0.59, P<0.05) and recovery muscles from the 13th to the 20th days (r=0.54, p<0.05), but in the tenotomized muscle from the operation to the 12th days the relationship between them completely disappeared (r=-0.29, p>0.05). These results suggest that the breakdown in the relationship between muscle CL and linoleic acid composition causes muscular atrophy induced by Achilles tendon tenotomy. Verf.-Referat