Intermittent and continuous haloperidol regimens produce different types of oral dyskinesias in rats.
Rats were administered equivalent doses of haloperidol for either 28 days or 8 months using one of two different drug regimens: intermittent (i.e., weekly injections) or continuously (via drinking water and osmotic mini-pumps). Oral movements were determined by human observers and by a computerized video analysis system, which determined number and amplitude of jaw openings and closings (computer-scored movelets "CSMs") as well as the slope (amplitude/duration) and frequency spectrum (fourier transform) of oral activity. The two drug groups developed distinctively different changes over time. Continuous administration resulted in late-onset oral activity changes at 1-3 Hz and withdrawal increases in CSMs, a pattern expected of tardive dyskinesia. Intermittent treatment produced a primed dystonia-like pattern: large amplitude CSMs which had steep onset slopes and a peak energy at 4-7 Hz. These results demonstrate the importance of drug regimen in determining the type of neuroleptic-induced dyskinesias which develop with prolonged neuroleptic treatment in rodents.
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Department of Psychology, University of California, Los Angeles 90024.
Ellison
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D000818:Animals; D001522:Behavior, Animal / Q000187:drug effects; D004409:Dyskinesia, Drug-Induced / Q000097:blood / Q000503:physiopathology*; D005260:Female; D005583:Fourier Analysis; D006120:Grooming / Q000187:drug effects; D006220:Haloperidol / Q000008:administration & dosage / Q000097:blood / Q000494:pharmacology*; D009043:Motor Activity / Q000187:drug effects; D051381:Rats; D011919:Rats, Inbred Strains
D006220:Haloperidol