Maria Franz finished her internship

In this research project the dynamics of Calcium as cellular messenger responsible for heart contraction is studied.The process of calcium flux in cardiac myocytes during depolarization is analyzed by computational tecniques in order to understand the influx and efflux through the cell membrane and the sarcoplasmic reticulum: influx of calcium coming from the extracellular medium - release of calcium of the SR by ryanodine receptors - increase of calcium concentration in the cytosol - reaching of the resting value by the action of Na-Ca and SERCA pumps. The opening of ryanodine receptors (RyR2) upon calcium-induced-calcium- release is studied using a Markov model for RyR2 gating and assuming stochastic transitients among different states. The calcium concentration in the different compartments can thus be modeled using a set of ordinary differential equations, coupled to the  a stochastic model of the RyR that will be solved using a Monte Carlo or Gillespie method.