INSULIN-LIKE-GROWTH-FACTOR-1 RESISTANCE IN CHRONIC-RENAL-FAILURE

Penal failure is characterized by endocrine and metabolic disorders, s ome of them being described as a state of resistance to growth hormone (GH) and/or insulin-like growth factor (IGF) 1. There is evidence for a reduced metabolic action of IGF-1 (formerly somatomedin C) in hemod ialysis and kidney transplant children and in adults undergoing hemodi alysis. Since the development of recombinant human (rh) IGF-1, despite strong metabolic actions, some experimental studies suggest a decreas e in metabolic effects of rhIGF-1 in chronic renal failure (CRF). Prel iminary reports in adult dialysis patients also stressed the possibili ty of a resistance to rhIGF-1 metabolic actions. The perturbed IGF-bin ding protein system in CRF may play an important role in modifying sto rage and IGF-I delivery to tissues. Also, by analogy with insulin, rec eptor and postreceptor defects may be involved in this condition, as s uggested by rhIGF-1 resistance with aging or in obese Zucker rats. How ever, rhIGF-1 remains a potent anabolic factor in uremia. Further stud ies will therefore be necessary to clarify this IGF-1 resistance state . Such knowledge might allow physicians to reduce the amount of rhIGF- 1 administered to the patients and improve the anabolic actions of rhI GF-1 during acute and chronic renal failure.