Evaluation neuroendocrinienne de la fonction catécholaminergique dans le comportement suicidaire

The current main neurochemical theories of the biological correlates of suicidal behavior principally involve the serotonergic system. Few data are available about the possible role of the catecholaminergic (noradrenergic and dopaminergic) function. In the present study we assessed the growth hormone (GH) response to clonidine, a selective alpha-2 - adrenergic agonist, and apomorphine, a dopaminergic agonist, in 15 DSM-III-R major depressive inpatients with a history of suicide attempts, compared to 15 age - and gender-matched major depressive inpatients without history of suicidal behavior. The two groups differed significantly in the GH peak response: after clonidine (mean ± SD), 2.93 ± 3.01 ng/ml in suicide attempters; and 8.28 ± 8.15 ng/ml in patients without history of suicide attempts; after apomorphine 6.29 ± 5.51 ng/ml and 17.45 ± 10.28 ng/ml. respectively. These results suggest that a blunted GH response to clonidine or to apomorphine could be biological correlates of suicidal behavior.