The effect of MK-801 and imipramine on beta-adrenergic and 5-HT2 receptors in the chronic mild stress model of depression in rats.

Chronic exposure (8 weeks) to sequential application of mild stressors caused the increase in the density (Bmax) of beta-adrenergic and 5-HT2 receptors in the rat cerebral cortex. MK-801 given chronically (5 weeks) decreased beta-adrenergic receptors density in both control and stressed rats, whereas it decreased the density of 5-HT2 receptors in control rats only. On the other hand, imipramine administered for 5 weeks reduced the number of beta-adrenergic and 5-HT2 receptors in both control and stressed rats.