L-dopa stimulates c-fos expression in dopamine denervated striatum by combined activation of D-1 and D-2 receptors.
Administration of L-dopa to unilaterally 6-hydroxydopamine-lesioned rats, activates the early gene c-fos in the lesioned caudate-putamen. D-1 receptor blockade by SCH 23390, prevented L-dopa-induced Fos-like immunoreactivity in the whole caudate-putamen, while D-2 receptor blockade by raclopride reduced Fos-like immunoreactivity only in the dorso-lateral portion. The results suggest that L-dopa induces c-fos primarily through an activation of D-1 receptors, while D-2 receptor stimulation plays a facilitatory influence on D-1-mediated c-fos expression.
Morelli
M
M
Department of Toxicology, University of Cagliari, Italy.
Cozzolino
A
A
Pinna
A
A
Fenu
S
S
Carta
A
A
Di Chiara
G
G
D000818:Animals; D001552:Benzazepines / Q000494:pharmacology; D003342:Corpus Striatum / Q000378:metabolism*; D003714:Denervation; D004298:Dopamine / Q000378:metabolism*; D065127:Dopamine D2 Receptor Antagonists; D007980:Levodopa / Q000494:pharmacology*; D008297:Male; D016760:Proto-Oncogene Proteins c-fos / Q000378:metabolism*; D020891:Raclopride; D051381:Rats; D017207:Rats, Sprague-Dawley; D011954:Receptors, Dopamine / Q000502:physiology*; D017447:Receptors, Dopamine D1 / Q000037:antagonists & inhibitors / Q000502:physiology; D017448:Receptors, Dopamine D2 / Q000502:physiology; D012457:Salicylamides / Q000494:pharmacology
D001552:Benzazepines; D065127:Dopamine D2 Receptor Antagonists; D016760:Proto-Oncogene Proteins c-fos; D011954:Receptors, Dopamine; D017447:Receptors, Dopamine D1; D017448:Receptors, Dopamine D2; D012457:Salicylamides; D020891:Raclopride; D007980:Levodopa; D004298:Dopamine