The perforated patch technique was utilized to obtain whole-cell currents from freshly dissociated rabbit corneal keratocytes. We describe and provide the initial characterization of two distinct whole cell currents in rabbit keratocytes: a K+-selective delayed rectifier and a voltage-sensitive, tetrodotoxin blockable Na+current. The voltage-sensitive Na+current is of sufficient magnitude to allow us to initiate action potentials when current-clamping the cells. This is the first detailed electrophysiological study of corneal keratocytes.