Partial 6-hydroxydopamine-induced lesions and haloperidol-induced catalepsy.
Rats with partial (36%) 6-hydroxydopamine-induced lesions of the striatal dopamine system or sham-lesioned controls were tested for duration of catalepsy after 1.0, 2.0 and 4.0 mg/kg haloperidol. Thereafter, half of each group was given haloperidol (2.0 mg/kg) chronically for 84 days. The cataleptic responses to the 3 doses were tested again on days 13-15 and 74-76 of the chronic injections. Animals that were lesioned and treated with haloperidol chronically had longer durations of catalepsy at the first two dose-response determinations. At the third dose-response determination, there were no differences among the 4 groups. Additionally, all groups displayed an increase in duration of catalepsy at the second and third dose-response determinations, relative to the first. The increase in haloperidol-induced duration of catalepsy in the lesioned group suggests that lower levels of dopamine in the striatum may potentiate extrapyramidal side-effects.
Johnson
S K
SK
Department of Psychology, Rutgers University, New Brunswick, NJ 08903.
Fisher
H
H
Wagner
G C
GC
D000375:Aging / Q000523:psychology; D000818:Animals; D001058:Apomorphine / Q000494:pharmacology; D001923:Brain Chemistry / Q000187:drug effects; D002375:Catalepsy / Q000139:chemically induced* / Q000473:pathology; D003342:Corpus Striatum / Q000187:drug effects / Q000378:metabolism; D004305:Dose-Response Relationship, Drug; D005260:Female; D006220:Haloperidol / Q000494:pharmacology*; D016627:Oxidopamine / Q000633:toxicity*; D051381:Rats; D017207:Rats, Sprague-Dawley
D016627:Oxidopamine; D006220:Haloperidol; D001058:Apomorphine