title: [The changes of funny currents in the ventricular myocytes of neonatal rats and adult rats].
abstract: OBJECTIVE
  To record funny currents (If) of ventricular myocytes and to analysize hyperpolarization-activated cation channel(HCN) expression in the rats of different ages.
  
  
  METHODS
  Fresh ventricular myocytes were isolated from 3 days rats and adult rats.HCN expressions were measured by real-time quantitative polymerase chain reaction(real-time PCR). It was recorded through whole-cell patch clamp.
  
  
  RESULTS
  HCN1, HCN2, HCN3, HCN4 mRNA represented 0.23% +/- 0.01%, 83.58% +/- 0.04%, 0.79% +/- 0.01%, 15.44% +/- 0.01% of total HCN mRNA in the neonatal rats, respectively. If was recorded and the threshold for activation was -75 mV. In the adult rat, HCN1, HCN2, HCN3, HCN4 mRNA represented 0.72% +/- 0.02%, 91.58% +/- 0.08%, 0.27% +/- 0.02%, 7.12% +/- 0.02% of total HCN mRNA. The ratio of HCN2 to HCN4 was approximately (13.06 +/- 0.21):1. The threshold for activation of If was approximately -115 mV in the adult rats.
  
  
  CONCLUSIONS
  With the development of rats, the value of If is smaller. The threshold for activation of If is more negative. The ratio of HCN2 to HCN4 is bigger.
authors.affiliation: Department of the Cardiology, The First Affiliated Hospital of Soochow University, Suzhou 215006, China.
authors.forename: Hong-xia
authors.initials: HX
authors.lastname: Li
authors.forename: Xiang-jun
authors.initials: XJ
authors.lastname: Yang
authors.forename: Xin
authors.initials: X
authors.lastname: Zhao
authors.forename: Ru-xin
authors.initials: RX
authors.lastname: Wang
authors.forename: Nin-zheng
authors.initials: NZ
authors.lastname: Dong
authors.forename: Lian-hua
authors.initials: LH
authors.lastname: Han
authors.forename: Ya-feng
authors.initials: YF
authors.lastname: Zhou
authors.forename: Bin
authors.initials: B
authors.lastname: Jiang
authors.forename: Wen-ping
authors.initials: WP
authors.lastname: Jiang
mesh_terms: D000367:Age Factors; D000818:Animals; D000831:Animals, Newborn; D002478:Cells, Cultured; D054815:Cyclic Nucleotide-Gated Cation Channels / Q000378:metabolism* / Q000502:physiology; D006352:Heart Ventricles / Q000166:cytology*; D064428:Hyperpolarization-Activated Cyclic Nucleotide-Gated Channels; D007473:Ion Channels / Q000378:metabolism; D032383:Myocytes, Cardiac / Q000166:cytology* / Q000502:physiology; D018408:Patch-Clamp Techniques; D015221:Potassium Channels / Q000378:metabolism* / Q000502:physiology; D012333:RNA, Messenger / Q000378:metabolism; D051381:Rats; D017207:Rats, Sprague-Dawley
chemical_list: D054815:Cyclic Nucleotide-Gated Cation Channels; C513836:HCN4 protein, rat; C578667:Hcn1 protein, rat; C578712:Hcn2 protein, rat; D064428:Hyperpolarization-Activated Cyclic Nucleotide-Gated Channels; D007473:Ion Channels; D015221:Potassium Channels; D012333:RNA, Messenger