Parametric resonance and amplification in excitable membranes. The Hodgkin-Huxley model.
It has previously been shown by different investigators that the excitable membrane shows a resonant sensitivity to periodic external perturbations, but its Q-factor is, as a rule, low. The present paper analyses the possible ways of increasing the membrane Q, using a model of the Hodgkin-Huxley type. It is found, in particular, that it can be increased considerably by modulating periodically the membrane capacitance or the activation and inactivation rate constants of ionic channels, with a frequency of about 2 fo (fo being the fundamental frequency of damped oscillations in the membrane), the extent of modulation not exceeding the critical value 2/Q. In this case, a significant parametric amplification of the membrane current takes place. If the modulation coefficient is above 2/Q, the membrane can display a parametric resonance that causes stable self-oscillations in the potential with a frequency approximately fo. The conditions for the realization of parametric amplification and resonance in biological membranes are discussed.
Markevich
N I
NI
Institute of Biological Physics of the USSR Academy of Sciences, Pushchino.
Sel'kov
E E
EE
D002462:Cell Membrane / Q000502:physiology*; D004558:Electric Stimulation; D004594:Electrophysiology; D007473:Ion Channels / Q000502:physiology; D008433:Mathematics; D008564:Membrane Potentials; D008954:Models, Biological
D007473:Ion Channels