"In Vivo" Effects of Lithium Sulphate on the Turnover of Rat Tissue Nucleotides

The effects of lithium sulphate following acute administration to Wistar rats - in therapeutic and toxic doses - were investigated, using as markers the levels and turnover of brain, kidney and liver nucleotides. Adenine- and guanine-dependent nucleotides were assayed concomitantly, using a high- performance liquid chromatographic method. Following acute administration, lithium's effects on 3',5'- cAMP levels were more significant at hepatic and cerebral level, in a dose-dependant manner. The effect on 3',5'-cGMP had tissue specificity and was not dose-dependant. It might be possible that 3',5'-cGMP is a better indicator of lithium toxicity than 3',5'-cAMP.