Odor discrimination in single turtle olfactory receptor neuron.

To explore the ability of odor discrimination of olfactory receptor neurons, current responses to odorant cocktails were recorded from an isolated olfactory neuron of the turtle. Twenty-five percent of the neurons tested responded to both cAMP-dependent and the IP3-dependent odorant cocktails. Application of the cAMP-dependent (or the IP3-dependent) odorant cocktail to the neuron after an inward current induced by the IP3-dependent (or the cAMP-dependent) odorant cocktail was adapted induced a large inward current in the neuron. The results suggest that at least two different receptors exist in a single olfactory neuron.