Figure 1.

Schematic representation of the groups used in the present study. In Experiment 1, four groups of paradoxical sleep-deprived (PSD) animals each were studied: Wistar-saline; Wistar-cocaine; SHR-saline and SHR-cocaine; another set of home-cage control (CTRL) and PSD of SHR and Wistar strains were used for hormonal assessment. Experiment 2: hormone-treatment SHR groups were used: vehicle; 25 mg/kg or 50 mg/kg of progesterone; 0.5 mg/kg or 1 mg/kg of testosterone. After the PSD period each group was then subdivided into saline or cocaine-challenged groups.