title: [Effects and mechanisms of low concentration dopamine on hydrogen peroxide-induced apoptosis in cultured neonatal rat cardiomyocytes].
abstract: OBJECTIVE
  To study the effects of low concentration dopamine(DA) on hydrogen peroxide-induced apoptosis in cultured rat cardiomyocytes as well as the possible molecular mechanisms.
  
  
  METHODS
  Cultured neonatal rat cardiomyocytes were randomly divided into the following groups: control group (control), hydrogen peroxide group (H2O2), pretreated with low concentration dopamine ( DA + H2O2), dopamine receptor l(DR1) antagonist group (DR1 + DA + H2O2), dopamine receptor 2(DR2) antagonist group (DR2 + DA + H2O2). The cell apoptosis was then assessed by MTT and flow cytometry. The cellular ultrastructure changes were observed by transmission electron micro- scope. The activity of lactate dehydrogenase(LDH )and superoxide dismutase (SOD) in cell medium was analyzed by colorimetry. The protein expressions of Cytochrone c, Caspase 3 and Caspase 9 were obtained by Western blot.
  
  
  RESULTS
  Compared with hydrogen peroxide group, low concentration dopamine(10 µmol/L) decreased the apoptosis rate and the expression of protein of apoptosis related protein, enhanced SOD activity, decreased LDH activity. DR1 antagonist SCH-23390 treatment inhibited dopamine induced cardiac protective effect. DR2 antagonist haloperido treatment had no changes compared with dopamine group.
  
  
  CONCLUSIONS
  Above findings indicate that low concentration dopanine inhibits apoptosis induced by hydrogen peroxide in neonatal rat cardiomyocytes, which is partly associated with the activation of DR1.
authors.forename: Xiao-na
authors.initials: XN
authors.lastname: Cai
authors.forename: Sa
authors.initials: S
authors.lastname: Shi
authors.forename: Hong-zhu
authors.initials: HZ
authors.lastname: Li
authors.lastname: Wang Li-na
authors.forename: Hong
authors.initials: H
authors.lastname: Li
mesh_terms: D000818:Animals; D017209:Apoptosis; D001552:Benzazepines; D053148:Caspase 3 / Q000378:metabolism; D053453:Caspase 9 / Q000378:metabolism; D002478:Cells, Cultured; D004298:Dopamine / Q000494:pharmacology*; D006861:Hydrogen Peroxide; D007770:L-Lactate Dehydrogenase / Q000378:metabolism; D032383:Myocytes, Cardiac / Q000187:drug effects*; D051381:Rats; D017208:Rats, Wistar; D017447:Receptors, Dopamine D1 / Q000378:metabolism; D013482:Superoxide Dismutase / Q000378:metabolism
chemical_list: D001552:Benzazepines; D017447:Receptors, Dopamine D1; C534628:SCH 23390; D006861:Hydrogen Peroxide; D007770:L-Lactate Dehydrogenase; D013482:Superoxide Dismutase; C505410:Casp3 protein, rat; C506435:Casp9 protein, rat; D053148:Caspase 3; D053453:Caspase 9; D004298:Dopamine