title: Effect of nicotine on dopamine uptake in COS cells possessing the rat dopamine transporter and in PC12 cells.
abstract: The effect of nicotine on the uptake of dopamine (DA) is not completely understood. We studied its effect on PC12 cells and on COS cells transfected with the rat DA transporter cDNA (pcDNADAT1). DA uptake by PC12 cells was inhibited by nicotine in a concentration-related fashion. Treatment of PC12 cells with nerve growth factor (NGF) increased such inhibition. This inhibitory effect was abolished by hexamethonium and mecamylamine, indicating that nicotine acted via the nicotinic acetylcholine (nACh) receptors in PC12 cells. This view is also supported by evidence that acetylcholine (ACh) reduced the uptake of DA in a hexamethonium-, but not atropine-, sensitive fashion. However, nicotine failed to inhibit DA uptake by COS cells possessing the DA transporter. These results suggest that the inhibitory effect of nicotine on DA uptake, when coupled with an nACh receptor leading to an indirect action on the transporter, may play a role in regulating extracellular concentrations of DA.
authors.affiliation: Third Department of Internal Medicine, Hiroshima University School of Medicine, Japan.
authors.forename: H
authors.initials: H
authors.lastname: Yamashita
authors.forename: S
authors.initials: S
authors.lastname: Kitayama
authors.forename: Y X
authors.initials: YX
authors.lastname: Zhang
authors.forename: T
authors.initials: T
authors.lastname: Takahashi
authors.forename: T
authors.initials: T
authors.lastname: Dohi
authors.forename: S
authors.initials: S
authors.lastname: Nakamura
mesh_terms: D000109:Acetylcholine / Q000037:antagonists & inhibitors / Q000494:pharmacology; D000818:Animals; D002118:Calcium / Q000172:deficiency; D002352:Carrier Proteins / Q000235:genetics / Q000378:metabolism*; D002460:Cell Line; D004298:Dopamine / Q000378:metabolism*; D050483:Dopamine Plasma Membrane Transport Proteins; D008562:Membrane Glycoproteins; D026901:Membrane Transport Proteins; D009414:Nerve Growth Factors / Q000494:pharmacology; D009419:Nerve Tissue Proteins; D009538:Nicotine / Q000037:antagonists & inhibitors / Q000494:pharmacology*; D016716:PC12 Cells; D051381:Rats; D014162:Transfection
chemical_list: D002352:Carrier Proteins; D050483:Dopamine Plasma Membrane Transport Proteins; D008562:Membrane Glycoproteins; D026901:Membrane Transport Proteins; D009414:Nerve Growth Factors; D009419:Nerve Tissue Proteins; D009538:Nicotine; D000109:Acetylcholine; D002118:Calcium; D004298:Dopamine