A new rodent model for neuroleptic-induced pseudo-parkinsonism: low doses of haloperidol increase forelimb tremor in the rat.
Rats were trained to use the right forelimb to exert continuous downward pressure on a force transducer and simultaneously to drink sweetened milk from a dipper controlled by the emitted force. Oscillations in forelimb force during this performance were spectrally analyzed to describe the tremorogenic effects of haloperidol (0.04, 0.08, or 0.16 mg/kg). Haloperidol reduced time-on-task and increased the variance of force oscillations in the 10.0-25.0-Hz frequency band. When atropine sulfate (5 mg/kg) was given along with haloperidol, time-on-task was partially restored, and the effects of haloperidol on the 10.0-25.0-Hz band were diminished. These data suggest that the behavioral deficits produced by relatively low doses of haloperidol in rats are analogous (and possibly homologous) to neuroleptic-induced Parkinsonian symptoms in humans.
Fowler
S C
SC
Department of Psychology, University of Mississippi, University 38677.
Liao
R M
RM
Skjoldager
P
P
D000818:Animals; D001285:Atropine / Q000494:pharmacology; D004195:Disease Models, Animal; D004305:Dose-Response Relationship, Drug; D004409:Dyskinesia, Drug-Induced / Q000209:etiology; D006220:Haloperidol / Q000633:toxicity*; D008297:Male; D010302:Parkinson Disease, Secondary / Q000139:chemically induced*; D011434:Proprioception / Q000187:drug effects; D011597:Psychomotor Performance / Q000187:drug effects; D051381:Rats; D011919:Rats, Inbred Strains; D014202:Tremor / Q000139:chemically induced*
D001285:Atropine; D006220:Haloperidol