Gender-dependent alterations in corticosteroid receptor status and spatial performance following 21 days of restraint stress.

The effects of 21-day exposure to restraint stress on hippocampal corticosteroid receptors and on spatial performance of male and female rats were evaluated. Stressed male animals exhibited a decrease in glucocorticoid receptor immunoreactivity in the CA1 area and the dentate gyrus. At the same time, stressed males tested on Morris water maze showed delayed learning and worse memory scores, compared with the control males. By contrast, stressed females exhibited an increase in glucocorticoid receptor immunoreactivity in CA1, similar learning ability and improved memory scores, compared with control females. In addition, stressed females showed a significant increase in mineralocorticoid receptor immunoreactivity in the CA3 area compared with controls. These data show that 21 days of restraint stress affect hippocampal corticosteroid receptors and spatial performance in a gender-specific manner. The observed changes in corticosteroid receptor levels following stress, may be causatively linked to the stress-induced alterations on spatial learning and memory.