Nicardipine protects against chronic ethanol- or haloperidol-induced supersensitivity to apomorphine-induced aggression.
Affective apomorphine-induced aggression was induced in originally nonaggressive rats after withdrawal from prolonged ethanol or haloperidol treatment. If the animals were co-administered Ca(2+)-channel blockers like diltiazem or verapamil the aggressive response to apomorphine was markedly decreased. Nicardipine (2 and 5 mg/kg b.i.d.) significantly attenuated the aggression-enhancing effect of chronic ethanol or haloperidol withdrawal in nonaggressive rats. Chronic nicardipine, alone, did not enhance aggressive behavior in the nonaggressive rats. Acutely, it suppressed apomorphine-induced aggression but did not alter open field activity when injected into aggressive rats. These results demonstrate that a Ca(2+)-channel blocker of the dihydropyridine type can prevent the development of an ethanol or haloperidol-withdrawal supersensitivity to apomorphine-induced aggression. It attenuates the aggression-inducing effect of apomorphine without impairing general activity.
Pucilowski
O
O
Center for Alcohol Studies, University of North Carolina School of Medicine, Chapel Hill 27599-7175.
Eichelman
B
B
D000374:Aggression / Q000187:drug effects*; D000818:Animals; D001058:Apomorphine / Q000494:pharmacology*; D001522:Behavior, Animal / Q000187:drug effects; D004347:Drug Interactions; D000431:Ethanol / Q000494:pharmacology*; D006220:Haloperidol / Q000037:antagonists & inhibitors* / Q000494:pharmacology; D008297:Male; D009529:Nicardipine / Q000494:pharmacology*; D011187:Posture; D051381:Rats; D011919:Rats, Inbred Strains; D014828:Vocalization, Animal / Q000187:drug effects
D000431:Ethanol; D009529:Nicardipine; D006220:Haloperidol; D001058:Apomorphine