Simultaneous Catalepsy and Apomorphine-induced Stereotypic Behavior in Mice

Intraventricular administration of haloperidol or chlorpromazine produces catalepsy and blocks apomorphine-induced stereotypic behavior. Low intraventricular doses of domperidone, sulpiride and spiperone, equally cataleptogenic as haloperidol or chlorpromazine, augment rather than diminish stereotypic behavior produced by subsequent apomorphine treatment. The resultant stereotypic behavior continues even while the animal is in a rigid cataleptic posture and is marked by persistent gnawing and licking. Prior to the induction of catalepsy and after recovery from it, mice display the entire range of typical apomorphine-induced behavior including sniffing, climbing, gnawing, and licking. This animal model may be related to the clinical observation of the coexistence of tardive dyskinesia and drug-induced Parkinsonism in individual patients.