Effects of the globus pallidus lesion on the induction of c-Fos by dopaminergic drugs in the striatum possibly via pallidostriatal feedback loops.
c-Fos is one of the transcription factors contributing to the regulation of the downstream gene expression. Administration of dopamine D1 receptor agonist or D2 receptor antagonist have been known to induce c-Fos expressions in striatal projection neurons. We examined the effects of unilateral ablation of the globus pallidus (GP) on apomorphine- or haloperidol-induced expression of c-Fos in the striatum. Haloperidol induced a high level of c-Fos expression in the striatal neurons, predominantly those in the dorsal part, and the unilateral GP lesion caused by ibotenic acid increased the number of neurons exhibiting haloperidol-induced c-Fos expression in the striatum on the side with the GP lesion by about 2- or 3-fold. On the other hand, the unilateral GP lesion had no significant effect on the apomorphine-induced c-Fos expression in the striatal neurons. The present study provides evidence indicating that the activity of GP neurons may have an inhibitory influence on the induction of the immediate early genes by haloperidol in the striatal neurons, suggesting a function of the pallido-striatal feedback loops which have been identified anatomically.
Miwa
H
H
Department of Neurology, Tokyo Metropolitan Institute for Neuroscience, Fuchu, Japan. h-miwa@med.juntendo.ac.jp
Fuwa
T
T
Nishi
K
K
Mizuno
Y
Y
D000818:Animals; D001931:Brain Mapping; D003342:Corpus Striatum / Q000187:drug effects / Q000378:metabolism*; D015259:Dopamine Agents / Q000494:pharmacology*; D005246:Feedback / Q000187:drug effects / Q000502:physiology; D005917:Globus Pallidus / Q000187:drug effects / Q000378:metabolism* / Q000502:physiology*; D006220:Haloperidol / Q000494:pharmacology; D008297:Male; D016760:Proto-Oncogene Proteins c-fos / Q000096:biosynthesis*; D051381:Rats; D017208:Rats, Wistar
D015259:Dopamine Agents; D016760:Proto-Oncogene Proteins c-fos; D006220:Haloperidol