膜電位に対する界面電位の寄与

静止電位および化学受容器電位の発生機序

抄録

In the field of physiology, it has generally been Considered that changes in the phase boundary potential do not affect membrane potentials. The present review shows that the phase boundary potential directly contributes to the membrane potential of a number of cells. (1) The K⁺-channels of mouse neuroblastoma (N-18 cells) are open at high external K⁺-concentration but closed at low K⁺-concentration including the physiological one. Under physiological conditions, the resting membrane potentials of N-18 cells stem significantly from the phase boundary potentials. Theoretical consideration shows that changes in the phase boundary potentials directly affect the membrane potential when no selective channels are open. (2) Changes in the phase boundary potential also contribute to the receptor potentials in taste cells, olfactory cells and Tetrahymena as well as to the resting potentials of these cells: adsorption of chemical stimuli on the receptor membranes of these cells induces changes in the phase boundary potential, which leads to depolarization of the cells.