Effect of adrenalectomy and corticosterone on [3H]imipramine binding in rat blood platelets and brain.

The effect of adrenalectomy and administration of glucocorticoids on [3H]imipramine binding (IB) of rat blood platelets and brain was investigated. Adrenalectomy significantly increased both Kd and Bmax of IB in the blood platelets but not the brain of male Sprague-Dawley rats. Administration of corticosterone acetate, 1 mg/kg i.p. for 7 days, decreased both Kd and Bmax in the blood platelets of sham-operated rats, but only Bmax in adrenalectomized rats. Corticosterone administration also decreased Bmax in frontal cortex and hypothalamus of sham and adrenalectomized rats but had no effect on Kd. These results suggest that glucocorticoids may modulate imipramine binding.