Simulation of extracellular electrical stimulation of rat optic nerve fiber based on experimental data / 中国组织工程研究

ABSTRACT

BACKGROUND:Currently,there are three types of visual prosthesisretinal prosthesis,optic nerve prosthesis and visual cortical prosthesis.Normal optic nerve fiber is the basis to apply visual prosthesis.Extracellular stimulation of myelinated optic nerve fiber is developed from intracellular stimulation,with feasible selection of stimulation locations and low requirements for operation.OBJECTIVE: Using computer to simulate the response of myelinated rat optic nerve fiber to extracellular point current source and to analyze the effect of the position of the point source on the response of the optic nerve fiber.METHODS:The experiment data of ion channels of rat optic nerve fiber and the characteristic of common ion channels were summarized,and the existing Hodgkin-Huxley like optic nerve fiber models were analyzed.The response of the optic nerve fiber model was simulated by computer,and the differences of action potentials of Ranvier node were compared by changing the position of point source.RESULTS AND CONCLUSION:Simulated models showed that the response of optic nerve is affected by the position of extracellular exciting electrode.The myelinated rat optic nerve fiber is easier to activate when the distance between point source and the Ranvier node center of the optic nerve fiber is short.