Increased cerebrospinal fluid levels of S100B protein in rat model of mania induced by ouabain.

Bipolar disorder is a chronic and severe mental disorder. Recently, new animal models have emerged to further investigate underlying mechanisms of bipolar disorder such as ouabain-induced hyperactivity in rats. In this study, we investigated the cerebrospinal fluid levels of S100B protein as a putative marker of astrocytic activity in bipolar mania induced by intracerebroventricular administration of ouabain in rats. Ouabain induced a two-fold increase in crossing responses in the open field test and increased 30% the cerebrospinal fluid concentration of S100B, as compared to vehicle group. Our findings reinforce the role of astroglial cells in the pathogenesis of bipolar disorder and S100B protein as a marker of bipolar mania.