RELATIONSHIP BETWEEN ALPHA(2)-ADRENERGIC FUNCTION AND SUICIDAL-BEHAVIOR IN DEPRESSED-PATIENTS

The current main neurochemical theories of the biological correlates o f suicidal behavior involve serotonergic and, to a lesser extent, dopa minergic systems. Few data are available about the possible implicatio n of the noradrenergic function. In the present study, we assessed the growth hormone response to clonidine, a selective alpha(2)-adrenergic agonist, in 15 DSM-III-R major depressive inpatients with a history o f suicide attempts, compared with 15 age- and gender-matched major dep ressive inpatients without a history of suicidal behavior. Mean (+/- S D) growth hormone peak responses to clonidine were significantly lower in the group of suicide attempters than in the control group: 2.93 +/ - 3.01 ng/ml vs. 8.28 +/- 8.15 ng/ml. Therefore, these results suggest that a blunted growth hormone response to clonidine could be a biolog ical correlate of suicidal behavior.