Nomifensine, a new antidepressant drug, affected the central noradrenergic neurons in the rat. Nomifensine did not affect the noradrenaline level in the brain, but retarded the depletion of noradrenaline after inhibition of its synthesis. Apomorphine and dimethylaminoadamantane, but not amphetamine, accelerated the depletion of noradrenaline. Nomifensine potentiated the flexor reflex of the hind paw of a spinal rat and depressed the body temperature.