Growth hormone response to clonidine after recovery in patients with endogenous depression.

The growth hormone response to clonidine was measured in ten drug-free recovered patients, seven of whom had previously been tested when endogenously depressed, and compared with the response in ten individually matched controls. In eight of the patients there was an impairment of the growth hormone response, despite clinical recovery, although the hypotensive effect of clonidine in these patients was normal. This is suggestive of a persisting abnormal alpha2-adrenoceptor function in forebrain regions after recovery from an episode of endogenous depression, and may represent a trait marker for this condition.