Measurement And Reconstruction Of Ion Channel Current For Cell Membrane In Rat's Cerebral Cortex

The ion channel of cell membrane is special protein molecule spanning the membrane of excitable cells. It is a basis of the cell electrical activity. And the gene variation and dysfunction of the ion channel can induce some diseases. At present, the study of ion channels had been a concerned focus in many fields. In order to record the ion channel currents with patch-clamp technique effectively, the measuring methods should be improved further. And with the purpose of studying the ion channel gating kinetics, ideal single channel current must be obtained. So reconstructing methods and building models for single channel current remain to be studied deeply. For exploring the bio-effects based on the physical factor, searching the more effective stimulus and induction styles, and revealing the effect law, it is necessary to study the features of ion channel current under the magnetic field irradiation. Against the problems of above, this paper performs in-depth research on ion channel of cell membrane. This work is shown as follows:(1) Obtain the neurons from the rat's athletic region of cerebral cortex by acute isolation, and the neurons must meet the demand for the patch-clamp experiment.(2) Study the patch-clamp theories and methods, the whole cell Na+ current and K+ current are detected separately with patch-clamp technique, and the time-dependency, activation characteristics and voltage-dependency of current are analyzed.(3) Record the voltage-gate Na+ current under the magnetic field irradiation, and the effects of magnetic field on Na+ current are analyzed. The results show that the amplitude of Na+ current is lower than control group. And it reveals that the magnetic field irradiation inhibits the opening of Na+ channel.(4) HMM is used to reconstruct ion single channel current simulated by computer. The experimental results show that the error ratio and iteration times increased along with the transition probability and signal-to-noise ratio (SNR) lowering. And compared with the threshold method, the signal can be restored finely under the lower SNR (SNR<5) by HMM.(5) Wavelet package algorithm is used to restore the ion single channel current. Compared with HMM algorithm, the wavelet package algorithm has the simple calculation, the faster convergence rate and high restoration precision, and can meet the demand for the patch-clamp system.The research has a foundation for analyzing ion channel and measuring ion current. And it provides a new method for detecting microcosmic information of ion channel on the cytology and molecules. Anyway, this research is valuable and meaningful for exploring the fabric and function of ion channel.