Ullman M, Oldfors A
Department of Pathology, Gothenburg University, Sweden.
Acta Physiol Scand. 1989 Apr;135(4):531-6. doi: 10.1111/j.1748-1716.1989.tb08612.x.
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.
