[Mechanism f kidney participation in maintaining osmotic and ion homeostasis in chronic renal failure].

In examination of patients with chronic renal failure (CRF) at glomerular filtration rate below 30 ml/min and blood serum ion concentration within limits of normal values hyperosmia has been found. Under the natural regimen essential differences have been revealed neither in variation limits of renal excretion of ions nor osmotically active substances in CRF patients as compared with healthy controls. Diuresis correlated with renal excretion of osmotically active substances. It is shown that a decrease in reabsorption of osmotically active substances depends on secretion and excretion of prostaglandin E2. A suggestion is made about the role of prostaglandins in regulation of renal tubular function at terminal CRF stages.