A parametric modeling of membrane current fluctuations with its application to the estimation of the kinetic properties of single ionic channels

摘要

A parametric autoregressive moving average (ARMA) signal modeling of membrane current fluctuations observed in biomembranes is described. Kinetic properties of single ionic channels contributing to membrane current fluctuations and the parameters of the corresponding ARMA process are explicitly related. The model is shown to be effectively applied to the estimation of the kinetic parameters of single ionic channels. Estimation of the parameters via ARMA signal identification is examined in detail for the basic closed-open scheme and the three-state sequential blocking scheme. The estimation accuracy of this method is theoretically evaluated. Computer simulation confirmed the validity of the proposed modeling and the effectiveness of the parametric method for the estimation of kinetic parameters when the model is applied to the estimation. The proposed modeling may form a theoretical base for the parametric analysis of membrane current fluctuations in a variety of kinetic schemes.