Voltage-clamp models for the study of acute and chronic effects of ethanol on ionic currents in adult mammalian neurons.

Abstract

The aim of this study was to develop and characterize a model system in which the effects of ethanol on voltage- and agonist-gated ionic currents in adult mammalian neurons could be studied using voltage-clamp techniques. We have found that neurons enzymatically isolated from the peripheral (nodose and superior cervical ganglia) and central nervous system (pyramidal layer of the hippocampus) of the adult rat and guinea pig provide several advantages over conventional neuronal preparations (e.g., intact ganglia or brain slice). First, the isolated neurons, in conjunction with the patch clamp technique, allow high fidelity recordings of both macroscopic and single channel currents. Secondly, current- and voltage-clamp recordings have revealed that active and passive membrane properties, chemosensitivity, and ionic currents in the isolated neurons resemble those described from conventional preparations. Finally, we have developed an intracellular perfusion system which allows the convenient control of the intracellular milieu. This technique should be useful for the study of intracellular second messengers on ionic currents. Our results demonstrate that isolated adult mammalian neurons are ideally suited for the study of both the acute and chronic effects of ethanol on membrane excitability.