Pharmacological studies on tandamine hydrochloride, a potential heterocyclic antidepressant.

Tandamine, a potential heterocyclic antidepressant, was compared with imipramine for its ability to modify: (a) the contractions induced by noradrenaline (NA) and 5-hydroxytryptamine (5-HT) on the normal and chronically denervated nictitating membrane of the cat, (b) the neuron blocking effect induced by guanethidine in the guinea pig vas deferens, (c) the electroencephalograph and the physostigmine arousal in the rabbit and (d) the sleep pattern of the rat. Both tandamine and imipramine potentiated the NA and 5-HT induced contractions of the normalnictitating membrane and antagonized the effects of gaunethidine on the vas deferens. The potentiation by tandamine and imipramine of the NA and 5-HT contraction of the nictitating membrane disappeared after chronic denervation of the membrane. These results are consistant with the ability of the substances to block the neural uptake of catechol- and indoleamines. Tandamine did not induce EEG synchronization and did not affect the arousal reaction induced by physostigmine. Tandamine also reduced or abolished REM (rapid eye movement) sleep with a concomitant decrease in NREM (non-rapid eye movement) sleep.