Modification of bone formation rate by growth hormone, melanocyte-stimulating hormone, and cortisone in the normal rat.

Bone growth and remodelling was studied in rats after injection of growth hormone, melanocyte-stimulating hormone (alpha-MSH), and cortisone daily for 20 days with tetracycline as intravital marker. An increase of both longitudinal and periosteal growth with growth hormone was found. A decrease of both was found after a high cortisone dose. Lower cortisone doses seem to have stimulated periosteal growth. No effect of alpha-MSH was found.