Clinical pathophysiology of the somatotropic (GH) axis in adults

In summary, GH secretion and, to a lesser extent, GH metabolic clearance, are subject to regulation in health and disease. Nutritional, body compositional, metabolic, and age-related and sex-steroid related mechanisms as well as adrenal glucocorticoids, thyroid hormones, and renal and hepatic function all govern pulsatile GH release in adults. Moreover, tissue resistance to GH action may occur as an inborn (Laron dwarf) or acquired (fasting, diabetes mellitus, chronic renal failure) defect and modulate the function of the somatotropic axis. Finally, GH action is controlled by the local synthesis of IGFs and their binding proteins in target tissues.