Analysis of intracellular recordings from salamander olfactory epithelium.

Intracellular recordings have been obtained from provisionally identified olfactory receptor and sustentacular cells in the salamander olfactory epithelium. Two categories of membrane potential transients were recorded intracellularly in response to odor stimulation. The first category of responses, presumably recorded from receptor cell somas, were monophasis positive spikes 10-50 mV in amplitude which were superimposed on a depolarizing slow potential which ranged from 4 to 8 mV in amplitude. Graded and differential responses were recorded in response to odor stimulation. The second category of responses were depolarizing and hyperpolarizing slow membrane potential transients presumably recorded from sustentacular cells. Spiking was not observed in response to odor stimulation. Pysiological criteria and Procion dye marking in several instances have provided evidence that responses in the first category were recorded from olfactory receptors and that certain of the other responses were recorded from sustentacular cells.