STABILITY ANALYSIS OF AN ELECTROCHEMICAL MODEL FOR EXCITABLE BIOMEMBRANES

Stability investigations at a membrane model are presented. The model includes a 4-state gating mechanism as instability-generating element. The gating mechanism is characterized by appropriate rate constants f or the ion channel rearrangement, and by changes of dipole charges. Th e influence of these physico-chemical parameters on the model dynamics was elucidated numerically. For the investigations a special strategy was developed which uses the eigenvalues for the discrimination of th e type of instability (oscillations or saddle point behaviour) occurri ng at given model conditions. The model calculations showed that a cha nge of the dipole charge by two units is sufficient for membrane oscil lations. This change could be realized, e.g. by association/dissociati on of a divalent ion at the end of an ion channel.