[Effect of lithium on water-salt metabolism in the frog Rana temporaria].

: Frogs kept in distilled water with 1 mM LiCl loose Na more readily than control animals in pure distilled water. After 10 days of staying in a medium with LiCl, a decrease of total content of Na and K in the body and skeletal muscles was observed together with a decrease in sodium content of the blood serum and intracellular concentration of potassium in muscles. There was no difference in the volume of extracellular fluid between the two groups of frogs. Concentration of Li in the blood serum was 5 times higher than that in the external medium, indicating active transport of Li across the skin. In skeletal muscle fibers, Li concentration was twice lower than in the blood serum. In frogs kept in LiCl solution, the increase in diuresis, as well as the increase in urinary excretion of Na and K were observed. It is suggested that Li ions inhibit sodium transport or prevent hormonal effects on the kidney, urinary bladder and skin of the frogs.