title: [Effect and mechanism of interleukin-2 on the rhythm of isolated rat heart and neonatal myocytes].
abstract: OBJECTIVE
  To explore the effect and mechanism of interleukin-2 (IL-2) on the rhythm of isolated rat heart and neonatal myocytes.
  
  
  METHODS
  Cultured neonatal rat cardiomyocytes and isolated perfused rat heart were used.
  
  
  RESULTS
  (1) IL-2 (2.5-200 u/ml) reduced the spontaneous beating rate of cultured neonatal rat cardiomyocytes in a dose-dependent manner. (2) IL-2 at 50 u/ml increased both the heart rate and the number of premature ventricular excitation in the isolated heart. (3) Pretreatment with propranolol abolished the effect of 50 u/ml IL-2 on the isolated heart. (4) Heat inactivated IL-2 had no significant effect on the cultured cardiomyocytes and isolated hearts.
  
  
  CONCLUSIONS
  IL-2 inhibited the auto rhythmic of cultured cardiomyocyte directly while the positive chronotropic and arrhythmogenic effects of IL-2 in the isolated rat heart may be mediated by endogenous catecholamine.
authors.affiliation: Department of Physiology, Zhejiang University School of Medicine, Hangzhou 310031, China.
authors.forename: Lin-Lin
authors.initials: LL
authors.lastname: Wang
authors.forename: Ying-Ying
authors.initials: YY
authors.lastname: Chen
authors.forename: Qiang
authors.initials: Q
authors.lastname: Xia
mesh_terms: D000818:Animals; D000831:Animals, Newborn; D002478:Cells, Cultured; D006321:Heart / Q000187:drug effects*; D006339:Heart Rate / Q000187:drug effects*; D066298:In Vitro Techniques; D007376:Interleukin-2 / Q000494:pharmacology*; D032383:Myocytes, Cardiac / Q000187:drug effects* / Q000502:physiology*; D011433:Propranolol / Q000494:pharmacology; D051381:Rats; D017207:Rats, Sprague-Dawley
chemical_list: D007376:Interleukin-2; D011433:Propranolol