Olfactory receptor cell activity under electrical polarization of the nasal mucosa in the frog. I. Spontaneous activity.

The electrical activity of single olfactory receptor cells was studied under electrical polarization of the olfactory epithelium in the frog. 1. The spontaneous discharge frequency varied as a linear function of the polarizing current in the range 1--20 X 10(--6)A. 2. Surface positive polarizations caused the spike activity to increase; surface-negative polarizations suppressed the activity. 3. Partial accommodation to the current was observed. 4. After-effects of short duration occurred: Rebound suppression after positive polarization, rebound excitation after negative polarization. 5. A high percentage of receptor units found in the frog's mucosa displayed no spontaneous activity.