activity of the electrogenic sodium, and potassium-activated adenosine triphosphatase membrane pump (Na, K-ATPase or Na pump) in acute mania relative to recovered euthymic bipolar individuals (Reddy et al., 1992; Scott and Reading, 1978; Hokin-Neaverson and Jefferson, 1989). Ouabain ICV administration in rats greatly increases locomotion, which may persist for several days after a single injection (Decker et al., 2000; Ruktanochai et al., 1998; Riegel et al., 2009), suggesting that the inhibition of Na, K-ATPase in the brain causes hyperactivity. These behavioral changes induced by ouabain can be preventable by mood stabilizing agents such as lithium, haloperidol and carbamazepine, (El-Mallakh et al., 2006; Li et al., 1997; Hennion et al., 2003). Together, this information supports the hypothesis that ICV administration of ouabain in rats can be considered a valid animal model of mania, since it mimics behavioral and biological aspects of a maniac state.