Differential expression of preproenkephalin and preprodynorphin mRNAs in striatal neurons: high levels of preproenkephalin expression depend on cerebral cortical afferents.
Preproenkephalin and preprodynorphin mRNAs can be detected by in situ hybridization in medium-sized striatal neurons in normal rats and in rats with unilateral cerebral cortical lesions. Hybridization of 35S-labeled oligonucleotide cDNAs complementary to specific regions of each mRNA reveals that preproenkephalin-expressing neurons are more numerous than cells expressing preprodynorphin. Hybridization densities above enkephalin-positive neurons are also more than twice those noted above preprodynorphin-expressing cells. Northern analyses of mRNA extracted from the striatum are consistent with these relationships. The striatal preproenkephalin hybridization densities are decreased ipsilateral to cerebral cortical lesions; this change evolves largely between 1 and 5 d following the lesion. Striatal preproenkephalin mRNA is thus more prominent than preprodynorphin mRNA and depends on cerebral cortical inputs for its full expression.
Uhl
G R
GR
NIDA, Department of Neurology, Johns Hopkins University School of Medicine, Baltimore, Maryland 21224.
Navia
B
B
Douglas
J
J
D000818:Animals; D015152:Blotting, Northern; D002540:Cerebral Cortex / Q000166:cytology / Q000378:metabolism*; D003342:Corpus Striatum / Q000166:cytology / Q000378:metabolism*; D004247:DNA; D004399:Dynorphins / Q000235:genetics / Q000378:metabolism*; D004745:Enkephalins / Q000235:genetics / Q000378:metabolism*; D008297:Male; D009474:Neurons / Q000378:metabolism; D009475:Neurons, Afferent / Q000378:metabolism; D009693:Nucleic Acid Hybridization; D011498:Protein Precursors / Q000235:genetics / Q000378:metabolism*; D012333:RNA, Messenger / Q000378:metabolism*; D051381:Rats
D004745:Enkephalins; D011498:Protein Precursors; D012333:RNA, Messenger; C036448:pre-prodynorphin; D004399:Dynorphins; D004247:DNA; C033660:preproenkephalin