Dopamine antagonist and "binge' cocaine effects on rat opioid and dopamine transporter mRNAs.
The modulation by selective dopamine receptor antagonists of the effects of "binge' cocaine (3 x 15 mg kg-1 day-1, i.p., for 3 days after 11 days of adaptation to saline injections) on preproenkephalin, preprodynorphin, kappa opioid receptor and dopamine transporter mRNAs was determined. Administration of cocaine was preceded by daily single injections of a D1 (SCH 23390; 2 mg kg-1) or the D2 (sulpiride; 50 mg kg-1) dopamine receptor antagonist. The D1, and not the D2, antagonist blocked cocaine-induced preprodynorphine and preproenkephalin increases in the caudate-putamen. Sulpiride alone, and sulpiride plus cocaine, increased preproenkephalin mRNA. Dopamine transporter mRNA levels showed a cocaine treatment-antagonist interaction. These data indicate that this administration paradigm elevates both preprodynorphin and preproenkephalin mRNAs by a D1-dependent mechanism not requiring D2 activation.
Spangler
R
R
Laboratory of the Biology of Addictive Diseases, Rockefeller University, New York, NY 10021, USA.
Zhou
Y
Y
Maggos
C E
CE
Zlobin
A
A
Ho
A
A
Kreek
M J
MJ
D000704:Analysis of Variance; D000818:Animals; D001552:Benzazepines / Q000494:pharmacology; D001921:Brain / Q000187:drug effects / Q000378:metabolism*; D002352:Carrier Proteins / Q000096:biosynthesis*; D003042:Cocaine / Q000008:administration & dosage / Q000494:pharmacology*; D017931:DNA Primers; D018492:Dopamine Antagonists / Q000494:pharmacology*; D050483:Dopamine Plasma Membrane Transport Proteins; D004334:Drug Administration Schedule; D004399:Dynorphins / Q000096:biosynthesis; D004745:Enkephalins / Q000096:biosynthesis; D008297:Male; D008562:Membrane Glycoproteins; D026901:Membrane Transport Proteins; D009419:Nerve Tissue Proteins; D016133:Polymerase Chain Reaction; D011498:Protein Precursors / Q000096:biosynthesis; D012333:RNA, Messenger / Q000378:metabolism; D051381:Rats; D011916:Rats, Inbred F344; D017473:Receptors, Opioid, kappa / Q000096:biosynthesis*; D019966:Substance-Related Disorders; D013469:Sulpiride / Q000494:pharmacology; D014158:Transcription, Genetic / Q000187:drug effects*
D001552:Benzazepines; D002352:Carrier Proteins; D017931:DNA Primers; D018492:Dopamine Antagonists; D050483:Dopamine Plasma Membrane Transport Proteins; D004745:Enkephalins; D008562:Membrane Glycoproteins; D026901:Membrane Transport Proteins; D009419:Nerve Tissue Proteins; D011498:Protein Precursors; D012333:RNA, Messenger; D017473:Receptors, Opioid, kappa; C036448:pre-prodynorphin; D004399:Dynorphins; D013469:Sulpiride; C033660:preproenkephalin; D003042:Cocaine