c-fos gene expression is induced in a subpopulation of striatal neurons following a single administration of a dopamine D1-receptor agonist in adult rats lesioned with 6-OHDA as neonates.
The effects of the dopamine D1 receptor agonist, SKF-38393, on the levels of mRNAs encoding for the proto-oncogene c-fos and the GABA-synthesizing enzyme glutamate decarboxylase (GAD65) were measured by in situ hybridization histochemistry in the striatum of adult rats depleted of dopamine as neonates. c-fos mRNA levels exhibited a prominent increase following the acute systemic administration of SKF-38393 in dopamine-depleted but not in normal rats. Double-labeling in situ hybridization histochemistry using a radioactive c-fos probe and a digoxigenin-labeled preproenkephalin (PPE) cRNA probe indicated that c-fos mRNA levels were increased by SKF-38393 exclusively in a subpopulation of PPE-unlabeled neurons. Dopamine-depleted rats exhibited an increase in GAD65 mRNA levels relative to control rats. Acute administration of SKF-38393 did not alter GAD65 mRNA levels in control or in dopamine-depleted rats. Our results demonstrate that an acute administration of a D1-receptor agonist induces c-fos but not GAD65 gene expression in a subpopulation of presumed striato-nigral/entopeduncular neurons. They also suggest that the D1-dependent behavioral plasticity exhibited by adult rats depleted of dopamine as neonates is not the result of an altered activation of the two subpopulations of striatal efferent neurons.
Soghomonian
J J
JJ
Department of Anatomy and Physiology, University Laval, Québec, Canada. jean-jacques.soghomonian@anm.ulaval.ca
Laprade
N
N
Sandstrom
M
M
Bruno
J P
JP
D015647:2,3,4,5-Tetrahydro-7,8-dihydroxy-1-phenyl-1H-3-benzazepine / Q000494:pharmacology; D000818:Animals; D000831:Animals, Newborn; D003342:Corpus Striatum / Q000737:chemistry / Q000166:cytology / Q000502:physiology*; D018491:Dopamine Agonists / Q000494:pharmacology; D005260:Female; D015971:Gene Expression Regulation, Enzymologic; D005968:Glutamate Decarboxylase / Q000235:genetics; D009474:Neurons / Q000737:chemistry / Q000201:enzymology; D016627:Oxidopamine; D011247:Pregnancy; D016760:Proto-Oncogene Proteins c-fos / Q000235:genetics*; D012333:RNA, Messenger / Q000032:analysis; D051381:Rats; D017207:Rats, Sprague-Dawley; D017447:Receptors, Dopamine D1 / Q000819:agonists*; D013565:Sympatholytics
D018491:Dopamine Agonists; D016760:Proto-Oncogene Proteins c-fos; D012333:RNA, Messenger; D017447:Receptors, Dopamine D1; D013565:Sympatholytics; D015647:2,3,4,5-Tetrahydro-7,8-dihydroxy-1-phenyl-1H-3-benzazepine; D016627:Oxidopamine; D005968:Glutamate Decarboxylase