Platelet adrenoceptors and prostaglandin responses in depressed patients.

Platelet alpha 2-adrenergic receptor binding and prostaglandin responsivity were measured in depressed patients. Depressed patients had significantly higher platelet 3H-dihydroergocryptine (3H-DHE) binding values than controls. Depressed patients also showed significantly reduced prostaglandin E1-stimulated cyclic adenosine 3',5'-monophosphate (cAMP) production and significantly decreased % inhibition of cAMP production by norepinephrine. These results support the suggestion that there may be a dissociation between alpha 2-adrenergic receptor binding and responsivity in depression. There were no significant correlations between platelet adrenergic variables and other indices of noradrenergic function. However, there was a significant correlation between 3H-DHE binding values and basal plasma levels of cortisol.