Avoidance facilitation by chlordiazepoxide-amphetamine combinations in mice: effect of alpha-methyl-p-tyrosine.

Chlordiazepoxide (CDP) and amphetamine (AMPH) were tested, alone or in combination, in BALB/c mice pretreated with alpha-methyl-p-tyrosine (AMT) and subjected to shuttle-box avoidance training. CDP and AMPH, given alone, partly reversed avoidance depression induced by 50 mg/kg of AMT, but were ineffective in mice pretreated with 100 mg/kg of AMT. Stronger effects were produced by CDP-AMPH combinations, which also improved avoidance performance in mice pretreated with the higher dose of AMT. The results suggest that catecholamines may play a role in the facilitation of avoidance induced by CDP, especially when given in combination with AMPH.