Regulation of amphetamine-stimulated dopamine efflux by protein kinase C beta.
Evidence suggests that protein kinase C (PKC) and intracellular calcium are important for amphetamine-stimulated outward transport of dopamine in rat striatum. In this study, we examined the effect of select PKC isoforms on amphetamine-stimulated dopamine efflux, focusing on Ca(2+)-dependent forms of PKC. Efflux of endogenous dopamine was measured in superfused rat striatal slices; dopamine was measured by high performance liquid chromatography. The non-selective classical PKC inhibitor Gö6976 inhibited amphetamine-stimulated dopamine efflux, whereas rottlerin, a specific inhibitor of PKC delta, had no effect. A highly specific PKC beta inhibitor, LY379196, blocked dopamine efflux that was stimulated by either amphetamine or the PKC activator, 12-O-tetradecanoylphorbol-13-acetate. None of the PKC inhibitors significantly altered [3H]dopamine uptake. PKC beta(I) and PKC beta(II), but not PKC alpha or PKC gamma, were co-immunoprecipitated from rat striatal membranes with the dopamine transporter (DAT). Conversely, antisera to PKC beta(I) and PKC beta(II) but not PKC alpha or PKCg amma were able to co-immunoprecipitate DAT. Amphetamine-stimulated dopamine efflux was significantly enhanced in hDAT-HEK 293 cells transfected with PKC beta(II) as compared with hDAT-HEK 293 cells alone, or hDAT-HEK 293 cells transfected with PKCa lpha or PKC beta(I). These results suggest that classical PKC beta(II) is physically associated with DAT and is important in maintaining the amphetamine-stimulated outward transport of dopamine in rat striatum.
Johnson
L'Aurelle A
LA
Department of Pharmacology, University of Michigan, Ann Arbor, Michigan 48109-0632, USA.
Guptaroy
Bipasha
B
Lund
David
D
Shamban
Susanna
S
Gnegy
Margaret E
ME
D000661:Amphetamine / Q000494:pharmacology*; D000818:Animals; D003342:Corpus Striatum / Q000201:enzymology; D004298:Dopamine / Q000378:metabolism*; D050483:Dopamine Plasma Membrane Transport Proteins; D005260:Female; D008562:Membrane Glycoproteins / Q000502:physiology; D026901:Membrane Transport Proteins / Q000502:physiology; D008698:Mesylates / Q000494:pharmacology; D009419:Nerve Tissue Proteins / Q000502:physiology; D011493:Protein Kinase C / Q000502:physiology*; D064546:Protein Kinase C beta; D011758:Pyrroles / Q000494:pharmacology; D051381:Rats; D017207:Rats, Sprague-Dawley; D013755:Tetradecanoylphorbol Acetate / Q000494:pharmacology
C434605:5,21 - 12,17-dimetheneo-18H-dibenzo(i,o)pyrrolo(3,4-1)(1,8)diazacyclohexandecine-18,10(19H)dione,8((dimethylamino)methyl)-6,7,8,9,10,11-hexahydro,monomethanesulfonate; D050483:Dopamine Plasma Membrane Transport Proteins; D008562:Membrane Glycoproteins; D026901:Membrane Transport Proteins; D008698:Mesylates; D009419:Nerve Tissue Proteins; D011758:Pyrroles; C493216:Slc6a3 protein, rat; D000661:Amphetamine; D011493:Protein Kinase C; D064546:Protein Kinase C beta; D013755:Tetradecanoylphorbol Acetate; D004298:Dopamine