Hormonal control of muscle growth.
In muscle of whole animals, pituitary growth hormone, the thyroid hormones, and insulin are major growth-promoting hormones, and the glucocorticoids have significant catabolic actions. At the cellular level the primary anabolic hormones for cultured myoblasts are the somatomedins (insulin-like growth factors) and fibroblast growth factor. In these cells physiological concentrations of growth hormone, thyroid hormones, and insulin have no growth-promoting effect; some of the reported actions of insulin probably result from cross-reaction with the somatomedin receptor. Results with purified proteins do not support the view that mitogens block myoblast differentiation; transforming growth factor-beta and interferon are nonmitogenic proteins that inhibit differentiation, insulin-like growth factors are mitogens that stimulate differentiation, and fibroblast growth factor is the only purified mitogen that inhibits differentiation. At least six serum-free media have now been devised for the growth of various kinds of muscle cells under closely defined conditions.
Florini
J R
JR
Biology Department, Syracuse University, NY 13244.
D000818:Animals; D002395:Catecholamines / Q000494:pharmacology; D002478:Cells, Cultured; D005938:Glucocorticoids / Q000502:physiology; D012739:Gonadal Steroid Hormones / Q000502:physiology; D013006:Growth Hormone / Q000502:physiology; D006133:Growth Substances / Q000502:physiology; D006728:Hormones / Q000502:physiology*; D006801:Humans; D007328:Insulin / Q000502:physiology; D024510:Muscle Development; D013002:Somatomedins / Q000502:physiology; D013963:Thyroid Hormones / Q000502:physiology
D002395:Catecholamines; D005938:Glucocorticoids; D012739:Gonadal Steroid Hormones; D006133:Growth Substances; D006728:Hormones; D007328:Insulin; D013002:Somatomedins; D013963:Thyroid Hormones; D013006:Growth Hormone