洞房結節細胞におけるβ1アドレナリン受容体刺激による陽性変時作用のシミュレーション研究

• 姫野 友紀子

  Grad. Sch. Med. Kyoto Univ., Kyoto, Japan

• 皿井 伸明

  Nano-Med. Merger Edu. Unit, Kyoto Univ., Kyoto, Japan

• 岡 千晶

  Grad. Sch. Med. Kyoto Univ., Kyoto, Japan

• 松岡 達

  Grad. Sch. Med. Kyoto Univ., Kyoto, Japan

• 野間 昭典

  Grad. Sch. Med. Kyoto Univ., Kyoto, Japan

書誌事項

タイトル別名

• A Simulation Study on Positive Chronotropy of SA Nodal Cell Induced by β1-adrenergic Stimulation

抄録

Positive chronotropy induced by β1-adrenergic stimulation is achieved by multiple interactions of ion channels and transporters in pacemaker cells. In order to investigate roles of the ion channels and transporters and their interactions in the chronotropy quantitatively, we updated our SA node cell model developed in 2003 and incorporated β1-adrenergic signaling cascade. Firstly, the validity of the model was reviewed by comparing behavior and parameters of the model with experimental data. Secondly, the response to β1-adrenergic stimulation was analyzed by isoprenaline (ISO) application, which enhanced multiple currents and increased firing frequency. From the analysis of enhanced currents during the stimulation, it was concluded that the L-type Ca²⁺ current (I_CaL), the sustained inward current (I_st) and the hyperpolarization-activated cation current (I_ha) played major roles in increasing the inward current during slow diastolic potential and thus increasing the firing rate. On the other hand, I_Ks was important to counterbalance increased inward currents especially in repolarizing phase of action potentials. The alteration of Ca²⁺ dynamics during the stimulation was also calculated in the model. It was suggested that the Ca²⁺ release from sarcoplasmic reticulum (SR) played a minor role in inducing chronotropic effect in our model. [J Physiol Sci. 2008;58 Suppl:S179]

収録刊行物

• 日本生理学会大会発表要旨集

  日本生理学会大会発表要旨集 2008 (0), 179-179, 2008

  一般社団法人　日本生理学会

キーワード

• SA node
• β1-adrenergic stimulation
• positive chronotropy
• simulation

詳細情報

• CRID: 1390282680705223296
• NII論文ID: 130005449816
• DOI: 10.14849/psjproc.2008.0_179_3
• データソース種別:
  • JaLC
  • CiNii Articles
• 抄録ライセンスフラグ: 使用不可