Nonlinear Dynamic Modeling of 2-Dimensional Interdependent Calcium and Inositol 1,4,5-Trisphosphate in Cardiac Myocyte
Nisha Singh, Neeru Adlakha
Sardar Vallabhbhai National Institute of Technology, Ichchhanath, Surat, Gujarat, India
Abstract. Calcium (Ca2+) and inositol 1,4,5-trisphosphate (IP3) is critically important actors for a vast array of cellular processes. The most significant of the functions is One of the main functions is communication in all parts of the body which is achieved through cell signaling. Abnormalities in Ca2+ signaling have been implicated in clinically important conditions such as heart failure and cardiac arrhythmias. We propose a mathematical model which systematically investigates complex Ca2+ and IP3 dynamics in cardiac myocyte. This two dimensional model is based on calcium-induced calcium release via inositol 1,4,5-trisphosphate receptors and includes calcium modulation of IP3 levels through feedback regulation of degradation and production. Forward-Time Centered-Space method has been used to solve the coupled equations. We were able to reproduce the observed oscillatory patterns in Ca2+ as well as IP3 signals. The model predicts that calcium-dependent production and degradation of IP3 is a key mechanism for complex calcium oscillations in cardiac myocyte. The impact and sensitivity of source, leak, diffusion coefficients on both Ca2+ and IP3 dynamics have been investigated. The results show that the relationship between Ca2+ and IP3 dynamics is nonlinear.
Key words: calcium and inositol 1,4,5-trisphosphate, signaling, cardiac myocyte, finite difference method, nonlinear coupled dynamics.