Quipazine exacerbation of a hyperkinetic syndrome: Involvement of brain dopamine and serotonin

Abstract

Quipazine (5–25 mg·kg⁻¹, s.c.) was given to rats in which a hyperkinetic syndrome had been previously induced by administration of β;,β′-iminodiproprionitrile (IDPN). Quipazine produced a significant increase in the circling behavior and choreiform head and neck movements, characteristic of the syndrome. This response could be blocked by pretreatment with the serotonin antagonists, SQ10, 631 (25 mg·kg ⁻¹, i.p.) and methysergide (5.0 mg·kg⁻¹, i.p.), as well as the dopamine receptor antagonist, haloperidol (0.5 mg·kg⁻¹, i.p.). These observations are discussed with respect to the nature of the involvement of brain serotonergic and dopaminergic systems in quipazine action on these hyperkinetic disturbances.