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<h4>Background</h4>Insect odorant receptors (ORs) function as odorant-gated ion channels consisting of a conventional, odorant-binding OR and the Orco coreceptor. While Orco can function as a homomeric ion channel, the role(s) of the conventional OR in heteromeric OR complexes has largely focused only on odorant recognition.<h4>Results</h4>To investigate other roles of odorant-binding ORs, we have employed patch clamp electrophysiology to investigate the properties of the channel pore of several OR complexes formed by a range of different odorant-specific Anopheles gambiae ORs (AgOrs) each paired with AgOrco. These studies reveal significant differences in cation permeability and ruthenium red susceptibility among different AgOr complexes.<h4>Conclusions</h4>With observable differences in channel function, the data support a model in which the odorant-binding OR also affects the channel pore. The variable effect contributed by the conventional OR on the conductive properties of odorant-gated sensory channels adds additional complexity to insect olfactory signaling, with differences in odor coding beginning with ORs on the periphery of the olfactory system.