DISSECTION OF A MODEL FOR MEMBRANE-POTENTIAL OSCILLATIONS IN BURSTINGNEURON OF SNAIL, HELIX-POMATIA

A slow-wave model for bursting activity based on the hyperpolarization -activated outward current has been analysed by simulation of the well -known experimental data. It is shown that the slow-wave model demonst rates an increase of membrane input resistance during the development of the depolarizing phase; responds adequately to stationary de- or hy perpolarizing current; demonstrates a phenomenon of induced hyperpolar ization and contingency. Change of definite model parameters selective ly affects burst or interburst interval, and the period of slow-wave o scillation. It is found that the investigated model, when using the sl owest process (1.5 sec) can generate persistent oscillations with a pe riod of more than 100 sec. Introduction of variable parameters in the model simulates an initiation of slow-wave oscillation in Helix bursti ng neuron evoked by stimulation of identified peptidergic interneuron. The limitation of the presented model of slow-wave oscillation is dis cussed.