The effects of lithium treatment on cation transport processes in erythrocytes of patients with affective illnesses.

The effect of lithium administration on cation transport processes in erythrocytes was investigated in 26 patients with affective illnesses. The measures of ouabain-dependent sodium and potassium transport, Na+K+ATP-ase activity and lithium-sodium countertransport in erythrocytes were taken before and after 14 days of lithium therapy. In eleven patients an additional assay was made, following 3-12 months of continuous lithium administration. A significant increase in sodium and potassium transport as well as Na+K+ATP-ase activity was found after 14 days of lithium therapy, while the intensity of lithium-sodium countertransport markedly decreased. Maintenance treatment with lithium tended to stabilize these changes on the altered level. A role of cation transport in the mechanism of lithium action is discussed. It is suggested that an increment of erythrocyte active cation transport may accompany the normothymic effect of lithium.