Effects of scopolamine and alpha-methylparatyrosine upon predatory attack in cats.

The effects of scopolamine were compared with the effects of alpha-methylparatyrosine methyl ester (AMPT) upon several aspects of electrically elicited predatory attack in cats. Thresholds of current necessary to elicit predation increased under both drugs. Furthermore, specific deficits developed in suprathreshold predatory patterns for both drugs compared with nondrug baselines. Scopolamine suppressed all aspects of attack, while AMPT suppressed approach of the attack object while leaving reflexive biting intact.