Formation of Behavioral Pathology in Female C57BL/6J Mice Exposed to Prolonged Negative Psychoemotional Conditions

Abstract

Prolonged exposure of females to negative psychoemotional conditions by permanent keeping with aggressive males on the other side of a perforated partition in a cage with daily witnessing of intermale confrontations had negative influences on the behavior of females, assessed using a variety of ethological tests. The elevated maze test and the open field test provided evidence for the development of marked anxiety in the females, with inhibition of motor and investigative activity. Decreases in the responses of females close to the partition to familiar and unfamiliar males one month after the onset of exposure to negative psychoemotional conditions and before the end of the experiment provided evidence for a decrease in communicativeness. After two months of exposure to negative psychoemotional conditions, intermale confrontations also ceased to interest females, as shown by the partition test. The hotplate test revealed worsening of pain sensitivity in experimental females. More than half of the individuals demonstrated impairment to the cyclicity of sexual cycles with increases in the duration of diestrus. After being kept in negative psychoemotional conditions, females ceased to differentiate littermates by social status and gender, as shown by social/sexual recognition tests. All these data provide grounds for suggesting the development of an anxious-depressive state in females after being kept in negative psychoemotional conditions for prolonged periods.