Two tests in rats for antianxiety effect of clinically anxiety attenuating antidepressants

The effects of mianserin, trazodone, amoxapine, maprotiline, and doxepin were assessed in punishment and pentylenetetrazol drug discrimination paradigms. These two procedures are used to identify antianxiety activity in rats. In the punishment procedure, misanserin produced an inverse dose-related increase in punished responding. The magnitude of the increase in punished responding with mianserin was comparable to that observed with the anxiolytic, buspirone. This effect was not observed with any of the other antidepressants tested. None of the antidepressants were found to be active in antagonizing the discriminative stimulus effects of pentylenetetrazol. In fact, at high doses there was a suggestion that the antidepressants may generalize to the pentylenetetrazol discriminative stimulus. Therefore, several antidepressants with purported clinical antianxiety activity, were not active in two procedures that detect antianxiety activity in rats.