Bromocriptine holiday: effects on dopamine receptors and turning behavior in rats
Kenny, A.M.; Schneider, M.B.; Baden, D.R.; Pfeiffer, R.F.; Murrin, L.C.
Neurology 36(3): 400-404
1986
ISSN/ISBN: 0028-3878 PMID: 3081831 Document Number: 267842
In experimental Parkinson's disease, we studied the effects of chronic administration (30 days), withdrawal, and reinstitution of bromocriptine. Dopamine (DA) receptor supersensitivity was produced by 6-hydroxydopamine and reversed by chronic bromocriptine administration. Drug holiday reestablished sensitivity of DA receptors, but reinstitution of bromocriptine again downregulated receptors. The effects of a drug holiday on DA receptors are short-lived, and long-term clinical improvement cannot be expected. Apomorphine-induced contralateral turning produced by the lesion was unaffected by any drug regimen.