The anterior gastric receptor (AGR neurone) participates to the control the gastric mill activity in the lobster. This neurone has a double branched dendrite; non linear current-voltage relationship results in spontaneous membrane potential oscillations for both branches. External stimulus on dendrites couples or uncouples the two oscillators. In addition, blood hormones modifies the current-voltage relationship. Consequently, time pattern of the AGR neurone action potentials reflects the level of excitation, the hormonal control and the coupling between dendritic oscillators; in turn AGR output controls gastric mill muscle activity.
A mathematical model for the AGR neurone electrical activity is derived from the Hodgkin-Huxley equations. Analysis of this model is carried out either by numerical simulations and by analytical study of a simplified version where the FitzHugh- Nagumo system replaces Hodgkin-Huxley equations.