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 beta,beta'-iminodipropionitrile (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.

The comparative roles of dopaminergic and serotonergic mechanisms in mediating quipazine induced locomotor activity

“…Other investigators have also variously characterized quipazine as a central DA agonist (q.v. Krause, 1976;Langlais and Gabay, 1977) including its ability to significantly enhance DA levels in the striatum (Miskiewicz et al, 1979), inhibit DA uptake (Mendon et al, 1973;Jacoby et al, 1976) and inhibit spiroperidol induced catalepsy in a dose-response manner (Grabowska et al, 1974).…”

“…In the present study, to further test the nature of the receptor involved in quipazine induced LA, the intracerebral injections of quipazine were preceded by saline, a specific central blocking agent (methysergide) or a central DA antagonist (haloperidol). Though haloperidol also inhibits central NE receptors at high doses, the low (0.25 mg/kg) dose used in the present study is thought to be specific to DA receptors alone (Langlais and Gabay, 1977).…”