The effects of twenty neuroleptic drugs on noise escape behavior were studied in rats trained to interrupt an aversive noise (95 decibels recycling every 20 sac) by jumping, in a shuttle box, from one compartment into the other. All twenty drugs prolonged the latency (T) and reduced the frequency (F) of the noise escape response rate.
Under the described experimental conditions, the order of potency of the 20 neuroleptics studied was: spiroperidol > spirilene > trifluperidol > benperidol > droperidol > spiramide > clofluperol ~> moperone > perphenazine > haloperidol ~> fluphenazine > amiperone > trifluperazine > pimozide ~> thioperazine > triflupromazine ~> fluanisone > chlorpromazine > pipamperone > thioridazine.
For all compounds tested, T was more sensitive to drug effect than F. Using the F 45/T 900 ratio, the order of specificity of the compounds studied was: pimozide > benperidol > spirilene > cloituperol > trifluperidol ~> haloperidol ~> fluphenazine ~> spiroperidol = pm~phenazine ~> moperone = trifluperazine = thioperazine ~> spiramide > amiperone ~> droperidol > triflupromazine ~> chlorpromazine >~ fluanisone > thioridazine ~ pipamperone.
As far as potency was concerned, there was a good correlation (r = 0.974) between the F 900-values of the noise escape test and the EDs0-values in the nondiscriminated Sidman avoidance test in rats and, as far as sedative properties were concerned, between the F 45/T 900 ratio and the palpebral ptosis/catalepsy ratio (r = --0.960) of the observation test in rats.