The effect of surgical trauma on muscle protein turnover in rats.
The rate of synthesis and catabolism of sarcoplasmic- and myofibrillar-muscle protein was measured in operated, sham-operated and food-restricted rats by using Na2 14CO3. The food-restricted group underwent sham operations and were limited to the food intake of the operated animals. Protein synthesis and catabolism were increased in the sarcoplasmic-muscle fraction in operated rats compared with that in sham-operated or food-restricted rats. The rate of synthesis of the myofibrillar protein decreased in operated animals, but the rate of catabolism was not altered in the myofibrillar-muscle fraction of the operated animals compared with that in food-restricted and sham-operated animals. In the operated animals, there was a net loss of protein from the muscle. Thus the rats that underwent surgery lost muscle protein, primarily as a result of a decrease in synthesis of myofibrillar protein. The changes in protein turnover in operated animals were not due to decreases in food intake, since protein turnover in sham-operated animals that were restricted to the food intake of the operated rats was not different from that in sham-operated rats fed ad libitum.
D000818:Animals; D001224:Aspartic Acid / Q000378:metabolism; D002254:Carbonates; D004032:Diet; D005260:Female; D005971:Glutamates / Q000378:metabolism; D009124:Muscle Proteins / Q000096:biosynthesis / Q000378:metabolism*; D009210:Myofibrils / Q000378:metabolism; D011184:Postoperative Period; D051381:Rats; D012519:Sarcoplasmic Reticulum / Q000378:metabolism; D013514:Surgical Procedures, Operative; D014599:Uterus / Q000601:surgery
D002254:Carbonates; D005971:Glutamates; D009124:Muscle Proteins; D001224:Aspartic Acid