The effect of amitriptyline on inhibitory avoidance in mice is dose-dependent.

The purpose of the present work was to study the dose-effect relationship of the antidepressant amitriptyline on inhibitory avoidance in male and female mice. Subjects received physiological saline or 2.5, 5, 10 or 20 mg/kg of amitriptyline hydrochloride 30 min before the training phase, and were subjected to the test phase 24 h later. Results showed a clear impairing effect of amitriptyline on inhibitory avoidance in both male and female mice, and that the effect is dose-dependent.