Cyclic Nucleotide Signaling Mediates an Odorant-suppressible Chloride Conductance in Lobster Olfactory Receptor Neurons

We have previously shown that lobster olfactory receptor neurons (ORNs) express an odorant-suppressible Cl− conductance that modulates the output of the cells. Here, we develop a more complete pharmacological profile of this conductance, showing it is blockable by the Cl− channel blockers DIDS, 9-AC and flufenamic acid, but not by niflumic acid. We then show that a conductance with this pharmacological profile is mediated by cyclic nucleotide signaling. These findings further our understanding of the cellular mechanisms through which odorants can modulate the output of lobster ORNs.