Hoover-Plow J L, Clifford A J
Biochem J. 1978 Oct 15;176(1):137-42. doi: 10.1042/bj1760137.
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.
通过使用Na2 14CO3,测定了手术大鼠、假手术大鼠和食物限制大鼠肌浆蛋白和肌原纤维蛋白的合成与分解代谢速率。食物限制组接受假手术,并限制其食物摄入量与手术动物相同。与假手术或食物限制大鼠相比,手术大鼠肌浆肌部分的蛋白质合成和分解代谢增加。手术动物的肌原纤维蛋白合成速率降低,但与食物限制和假手术动物相比,手术动物肌原纤维肌部分的分解代谢速率没有改变。在手术动物中,肌肉出现蛋白质净损失。因此,接受手术的大鼠肌肉蛋白流失,主要是由于肌原纤维蛋白合成减少。手术动物蛋白质周转的变化并非由于食物摄入量减少,因为食物摄入量限制在手术大鼠水平的假手术动物的蛋白质周转与自由进食的假手术大鼠没有差异。