Odorant Detection by a Given Olfactory Receptor Neuron Could Be

Question

Odorant detection by a given olfactory receptor neuron could be monitored (at least in theory) by: A) an increase in internal cAMP. B) an increase in internal Ca²⁺. C) an increase in internal Na⁺. D) a decrease in internal Cl^-. E) All of the above

Accepted Answer

Odorant binding to a G-coupled-receptor activates GF1F1F1S1F1F1F10_olf, which activates ACIII, converting ATP to cAMP. cAMP binding causes a cyclic nucleotide-gated channel to open, allowing the influx of Ca²⁺ and Na⁺. Ca²⁺opens a channel that allows efflux of Cl^-, further depolarizing the ORN.