[Extrarenal factors regulating the concentration of osmotically active substances and sodium in blood].

After feeding without water the concentration of osmotically active substances changed by 10--12 mosm/l in the blood serum of rabbits and rats. Bilateral section of the renal crus led to osmotic changes in serum after administration of water or sodium solution during first 15 min which disappeared within 45 min. Large concentrations of sodium solution induced considerable changes in these animals which still were lesser than could have been expected. The data obtained emphasize significance of extrarenal factors for regulation of shifts occurring in disturbances of osmotic and ion balance.