Lack of pineal beta-adrenergic receptor alterations in suicide victims with major depression

Noradrenergic function may be altered in depressive illness and thereby contribute to decreased pineal production of melatonin levels, as previously described in some depressed subjects. In the present study, the hypothesis was tested that pineal beta-adrenergic binding would be increased in persons committing suicide with evidence of depressive disorders, reflecting diminished noradrenergic input. Initially, post-mortem human pineal glands were obtained at autopsy. Diagnostic and symptomatic information was then systematically collected from family members using standardized interview techniques. Seven subjects who committed suicide and suffered from major depression, and without exposure to treatment for depressive symptoms were age- and sex-matched with control subjects. Pineal beta-adrenergic binding was assessed by quantitative autoradiography employing four concentrations of [125I]pindolol. Because of possibly complex adrenergic regulation of the pineal, beta-adrenergic receptor binding were subtyped using the selective blocker ICI 89406. No differences in beta-adrenergic receptors were detected between subjects with major depression compared to the matched controls.