Dopaminergic supersensitivity after long-term bromopride treatment.
The effects of bromopride administration on open-field and apomorphine-induced stereotyped behavior of rats were studied. Bromopride induced a displacement to the right of the control dose-response curve constructed for apomorphine stereotypes. Withdrawal from long-term bromopride treatment induced not only a significant increase in ambulation and rearing frequencies for male rats observed in the open-field but also an increased sensitivity of both male and female animals to apomorphine. The results are interpreted as a consequence of the development of supersensitivity of central dopaminergic receptors, probably of the mesostriatal pathways.
Clinical Pharmacology and Toxicology, School of Veterinary Medicine, University of São Paulo, Brazil.
L F
LF
Felicio
A G
AG
Nasello
J
J
Palermo-Neto
D000818:Animals; D001058:Apomorphine / Q000494:pharmacology; D004298:Dopamine / Q000502:physiology*; D004334:Drug Administration Schedule; D005260:Female; D008297:Male; D008787:Metoclopramide / Q000008:administration & dosage / Q000031:analogs & derivatives* / Q000494:pharmacology; D009043:Motor Activity / Q000187:drug effects*; D051381:Rats; D011919:Rats, Inbred Strains; D012737:Sex Factors; D013239:Stereotyped Behavior / Q000187:drug effects*
C013855:bromopride; D008787:Metoclopramide; D001058:Apomorphine; D004298:Dopamine