Influence of circadian phase on the magnitude of stress-alcohol cross-sensitization in male versus

The body’s internal clock influences when and how stress responses occur in both humans and laboratory animals, with evidence indicating that the depressive-like effects of repeated stressor exposure are more pronounced when experienced by nocturnal rodents (e.g., mice).Repeated stress increases behavioral sensitivity to alcohol (a.k.a. cross-sensitization). Although stress responsiveness varies with the circadian cycle, the influence of circadian phase on stress-alcohol cross-sensitization is unknown. This project will use a mouse model of repeated, unpredictable, mild stress (RUMS) to compare the effects of circadian phase on the behavioral sensitivity to alcohol via locomotor hyperactivity, intoxication, and sedation. As females tend to be more sensitive to the behavioral effects of alcohol than males, this project will include both sexes to examine for potential interactions between circadian phase and sex differences in gating the effects of RUMS on alcohol-induced motor behavior.