Frequency switches in inhibitory networks with anesthetics

We examine how synaptic depression resulting from desensitization (as modelled by a kinetic scheme for GABA, synapses), affects the coherent frequency produced by inhibitory networks. Analytical work using a phenomenological model of synaptic depression shows that different mechanisms are invoked in determining the synchronized frequency. Numerical simulations with the receptor desensitization model show that behaviours predicted by the analytical work are obtained when desensitization is modulated as occurs with anesthetics. Our results suggest that the coherent frequency of inhibitory networks is very sensitive to desensitization. Thus, the effects of different anesthetics on desensitization may contribute to their differential neurodepressive effects. (C) 2001 Elsevier Science B.V. All rights reserved.