Lithium induces phosphoglucomutase activity in various tissues of rats and in bipolar patients.

Phosphoglucomutase catalyses the reversible conversion of glucose-6-P and glucose-1-P. Lithium is a potent inhibitor of phosphoglucomutase in vitro, however, it is not known if phosphoglucomutase was significantly inhibited by Li+ in Li+-treated bipolar patients. Here, we demonstrate that phosphoglucomutase inhibition by chronic Li+ treatment causes alterations of glucose-phosphate levels in various tissues of rats. Also, phosphoglucomutase inhibition results in compensatory elevation of phosphoglucomutase activity in rat tissues and in leukocytes isolated from Li+-treated bipolar patients. The increase of uninhibited phosphoglucomutase activity in leukocytes of Li+-treated bipolar patients is due to the increased expression of the PGM1 gene.