To study the association between somatomedin-like activity (SMLA) and overload-induced increases in muscle weight, SMLA in soleus muscles and blood plasma was determined in hypophysectomized rats following tenotomy of the gastrocnemius. The incorporation of 3H-thymidine into chick embryo fibroblasts was used to estimate SMLA. In 10 rats baseline values for SMLA were determined without tenotomy; in 19 rats SMLA was determined 3 days following tenotomy. Soleus muscles from tenotomized limbs were 24% heavier (p < .001) than contralateral controls. The SMLA in soleus muscles from tenotomized limbs was 50% greater (p < .01) than SMLA in contralateral control limbs. Similarly, plasma SMLA from the tenotomized group was 77% greater (p < .05) than plasma SMLA in the baseline group. In 22 of 26 cases where data for both left and right soleus muscle were obtained, the heavier muscle had greater SMLA. It is concluded that there is a substantial association between SMLA and overload-induced muscular hypertrophy.
|Original language||English (US)|
|Number of pages||1|
|Journal||IRCS Medical Science|
|State||Published - Jan 1 1981|
ASJC Scopus subject areas
- Biochemistry, Genetics and Molecular Biology(all)