In the biosocial model of Cloninger, the three personality dimensions are related to different central neurotransmission systems. In agreement with this model, a recent study (Wiesbeck et al., 1995) showed an association between growth hormone response to apomorphine, an indirect assessment of the dopaminergic system, and novelty seeking score in alcohol-dependent men. In the present study we investigated the same methodology in a sample of major depressive patients. In addition, we assessed the relationship between noradrenergic function and Cloninger's dimensions using the clonidine test, an indirect assessment of the noradrenergic system. Growth hormone responses to apomorphine and clonidine were not associated with novelty seeking, reward dependence or harm avoidance dimension scores. This study therefore does not confirm the results of Wiesbeck et al. (1995), and does not support an association between noradrenergic activity and reward dependence dimension. However, given the complexity of central neurotransmission systems and the limitations of neuroendocrine challenges for the assessment of those processes, this study could not be considered as definitive evidence against the association between personality dimensions and their hypothesized central substrates.