title: Dopamine D1 receptor activation induces dehydroepiandrosterone sulfotransferase (SULT2A1) in HepG2 cells.
abstract: OBJECTIVE
  Dopamine receptors are present in the nervous system and also widely distributed in the periphery. The aim of this study was to investigate the role of D1 subtype dopamine receptors (DRD1) in the regulation of dehydroepiandrosterone sulfotransferase (SULT2A1) in HepG2 cells.
  
  
  METHODS
  HepG2 cells were treated with DRD1 agonists with or without DRD1 antagonist for 9 d. DRD1 and SULT2A1 mRNA expression, protein expression, and SULT2A1 activity were detected using RT-PCR, Western blotting and HPLC, respectively. The level of cAMP was measured using a commercial kit.
  
  
  RESULTS
  All the 5 DR subtypes (DRD1-DRD5) were found to be expressed in HepG2 cells. Treatment of HepG2 cells with the specific DRD1 agonists SKF82958 (2.5 μmol/L) or SKF38393 (5 and 50 μmol/L) significantly increased the mRNA and protein expression of both DRD1 and SULT2A1, and increased SULT2A1 activity and cAMP levels. These effects were partially blocked by co-treatment with the specific DRD1 antagonist SCH23390 (2.5 μmol/L). In addition, transfection of HepG2 cells with DRD1-specific siRNAs decreased DRD1 mRNA expression by 40%, which resulted in the reduction of SULT2A1 mRNA expression by 60%, protein expression by 40%, and enzyme activity by 20%.
  
  
  CONCLUSIONS
  DRD1 activation upregulates DRD1 and SULT2A1 expression and SULT2A1 activity in HepG2 cells, suggesting that the DRD1 subtype may be involved in the metabolism of drugs and xenobiotics through regulating SULT2A1.
authors.forename: Jiao-Jiao
authors.initials: JJ
authors.lastname: Xu
authors.forename: Si-Yuan
authors.initials: SY
authors.lastname: Wang
authors.forename: Ye
authors.initials: Y
authors.lastname: Chen
authors.forename: Guang-Ping
authors.initials: GP
authors.lastname: Chen
authors.forename: Zai-Quan
authors.initials: ZQ
authors.lastname: Li
authors.forename: Xue-Yan
authors.initials: XY
authors.lastname: Shao
authors.forename: Liang
authors.initials: L
authors.lastname: Li
authors.forename: Wei
authors.initials: W
authors.lastname: Lu
authors.forename: Tian-Yan
authors.initials: TY
authors.lastname: Zhou
mesh_terms: D004789:Enzyme Activation / Q000187:drug effects; D015971:Gene Expression Regulation, Enzymologic / Q000187:drug effects*; D056945:Hep G2 Cells / Q000187:drug effects* / Q000201:enzymology / Q000378:metabolism; D006801:Humans; D012333:RNA, Messenger / Q000235:genetics; D017447:Receptors, Dopamine D1 / Q000819:agonists* / Q000037:antagonists & inhibitors / Q000378:metabolism*; D015238:Sulfotransferases / Q000235:genetics / Q000378:metabolism*; D015854:Up-Regulation / Q000187:drug effects
chemical_list: D012333:RNA, Messenger; D017447:Receptors, Dopamine D1; D015238:Sulfotransferases; C028152:alcohol sulfotransferase