The synaptic basis of general anaesthesia.

The cellular and synaptic mechanisms that underpin the state of general anaesthesia are discussed. Anaesthetics act principally on synaptic processes and this provides a satisfactory basis for understanding their effects on neural networks. Although anaesthetics affect both the release of neurotransmitters and post-synaptic receptor function, the effects on post-synaptic receptors are always of importance in the modulation of synaptic transmission. Effects on action potential firing patterns also play a role in anaesthetic modulation of neuronal signalling. Many of these complex data can be explained in terms of altered ion channel function.