Effects of dextroamphetamine, lithium chloride, sodium valproate and carbamazepine on intraplatelet Ca2+ levels.

To explore the possible involvement of second-messenger pathways in the pathophysiology of bipolar disorder and the mechanism of action of mood stabilizer, we investigated the effects of dextroamphetamine (a model for mania) and the most widely used mood stabilizers, lithium chloride, sodium valproate and carbamazepine, on intraplatelet levels of calcium ion. In the first part of the study, dextroamphetamine was administered in vivo in a double-blind, placebo-controlled, crossover design. In the second part of the study, platelets from untreated subjects were incubated in vitro with dextroamphetamine, lithium chloride, sodium valproate or carbamazepine. 15 men aged 18-45 yrs participated. In vivo administration of dextroamphetamine had no effect on basal or agonist-induced intraplatelet calcium ion. In vitro basal platelet calcium ion was significantly higher in samples incubated with dextroamphetamine, lithium chloride, sodium valproate and carbamazepine. The modulation of intraplatelet calcium ion by the mood stabilizers lithium chloride, sodium valproate and carbamazepine implicates intracellular calcium ion in the therapeutic mechanisms of these drugs and the pathophysiological basis of mania. (PsycInfo Database Record (c) 2021 APA, all rights reserved)