MODULATION OF PROTEIN KINETICS IN CHRONIC-RENAL-FAILURE

Many factors are involved in inducing muscle wasting and derangements of protein metabolism in chronic renal failure. Anorexia, low protein intake, hormonal abnormalities (increased cortisol and parathyroid hor mone secretion, and insulin resistance), acidosis, abnormalities of th e cytokine system, and other unidentified uremic toxins create a negat ive nitrogen balance and stimulate protein catabolism. The protein tur nover rate (i.e., synthesis and degradation) is generally decreased in non-acidotic uremic patients. However, in uncorrected acidosis, prote in degradation is accelerated and a rapid loss of body proteins superv enes. Nutrition can be improved in chronically uremic patients through pharmacological therapy that can control protein catabolism. Administ ration of growth hormone and insulin-like growth factor-1 has been sho wn to be effective. These hormones influence both glucose and glutamin e metabolism. Another approach is the administration of pentoxifylline , which may have an anticatabolic effect by interfering with the tumor necrosis factor-alpha system.