抄録
Excitation of membranes is usually interpreted by two kinds of theory. One of them is the change of permeability coefficient of Hodgkin & Katz. The other is the opening and closing of ionic channels. If these two theories are to be compatible, the permeability coefficient of Hodgkin & Katz ought to be correlated with the opening and closing of ionic channels. In this paper, the correlation between them are theoretically discussed and a study of the excitation of membrane is developed.
As the result, it is pointed out that the Goldman-Hodgkin-Katz equation fails to explain the experimental results on the excitation of membrane (for example, excitation of squid giant axon), if the membrane model which is usually used as the theoretical model since Teorell and Meyer & Sievers, bulk soln. //membrane// bulk soln., is used as the theoretical model. We, therefore, propose a sublayer model of membrane, bulk soln. /sublayer//membrane//sublayer/bulk soln., together with the following assumptions : i) The membrane has ionic channels. ii) The membrane has electric charge and its density is θM (algebraic). iii) A Donnan equilibrium condition is set up between the sublayer and the bulk solution. iV) Ions in the sublayer are adsorbed on the surface of specific ionic channels and permeate through these channels. V) The electric potential in the sublayer is equal to that at the membrane surface.
On the basis of this sublayer model, we conclude that the permeability coefficient of Hodgkin & Katz is related to the number of open ionic channels, so that the permeability coefficient changes with opening and closing of the ionic channel.
