Effects of growth hormone on skeletal muscle. I. Studies on normal adult rats.
A study was made on the effects of recombinant human growth hormone (rhGH) on fast and slow skeletal muscle in normal adult female rats. Daily injections of 4 IE of rhGH over 36 days resulted in increased levels of insulin-like growth factor I in serum and increased body weight. Morphometric analysis of the muscle fibres of the extensor digitorum longus (EDL) and soleus muscles revealed a significant increase in diameter of both type 1 and type 2 fibres in both muscles. The DNA: protein ratio and the number of satellite cells:muscle fibre in cross-sections was increased in the GH-treated rats in relation to controls. The results show that rhGH has pronounced effects on both cell proliferation and muscle fibre growth in skeletal muscle of normal adults rats.
Ullman
M
M
Department of Pathology, Gothenburg University, Sweden.
Oldfors
A
A
D000818:Animals; D001835:Body Weight / Q000187:drug effects; D002452:Cell Count; D002455:Cell Division / Q000187:drug effects; D004247:DNA / Q000032:analysis; D005260:Female; D013006:Growth Hormone / Q000008:administration & dosage*; D007334:Insulin-Like Growth Factor I / Q000097:blood; D009132:Muscles / Q000187:drug effects*; D009929:Organ Size / Q000187:drug effects; D051381:Rats; D011919:Rats, Inbred Strains
D007334:Insulin-Like Growth Factor I; D013006:Growth Hormone; D004247:DNA