Weather change and Mood Disorder

Abstract

Mood disorder such as depression is serious problem in today’s society. Weather change has been known to influence the condition of patients with mood disorder, and the seasonality in the evolvement of depressive symptoms. However, no animal studies have tested the influence of climatic factor on emotional impairment. Therefore, we examined the effect of lowering barometric pressure (LP) in a climate-controlled room on immobility time in the forced swim test in rats, which is considered to be an index of behavioral despair (helplessness). Our findings demonstrated that LP in the range of natural weather change (20 hPa below the atmospheric pressure) augmented the depression-like behavior in rats.