Summary
International Symposium on Nonlinear Theory and Its Applications
2016
Session Number:A4L-F
Session:
Number:A4L-F-3
Mechanisms of Sinoatrial Node Pacemaking: Novel Insights Into Roles of the Pacemaker Current $I_f$ from Bifurcation Analysis of Mathematical Models
Yasutaka Kurata, Ichiro Hisatome, Toshishige Shibamoto,
pp.-
Publication Date:2016/11/27
Online ISSN:2188-5079
Summary:
To elucidate dynamical mechanisms of sinoatrial node (SAN) pacemaking with special focus on roles of hyperpolarization-activated current (If), we investigated influences of If on parameter-dependent stability and bifurcations of SAN cells, whether blocking If abolishes SAN pacemaking, and effects of If-dependent changes in intracellular Na+ concentration (Nai). Bifurcation analyses were performed for mathematical models of rabbit SAN cells. We conclude that 1) blocking If abolishes SAN pacemaking only when cells are hyperpolarized; 2) overlarge If does not enhance but attenuates robustness of SAN cells; and 3) enhancing effect of If on SAN robustness is reversed by elevations in Nai.