Editing Olfactory receptor neuron (section)

===Desensitization===
The olfactory receptor neuron has a fast working negative feedback response upon [[depolarization]]. When the neuron is depolarizing, the [[CNG ion channel]] is open allowing [[sodium]] and [[calcium]] to rush into the cell. The influx of calcium begins a cascade of events within the cell. Calcium first binds to calmodulin to form [[CaM]]. CaM will then bind to the CNG channel and close it, stopping the sodium and calcium influx.<ref>{{cite journal | last1 = Bradley | first1 = J | last2 = Reuter | first2 = D | last3 = Frings | first3 = S | year = 2001 | title = Facilitation of calmodulinmediated odor adaptation by cAMP-gated channel subunits | journal = Science | volume = 294 | issue = 5549| pages = 2176–2178 | doi=10.1126/science.1063415 | pmid=11739960| bibcode = 2001Sci...294.2176B | s2cid = 13357941 }}</ref> [[CaMKII]] will be activated by the presence of CaM, which will phosphorylate ACIII and reduce cAMP production.<ref>{{cite journal | last1 = Wei | first1 = J | last2 = Zhao | first2 = AZ | last3 = Chan | first3 = GC | last4 = Baker | first4 = LP | last5 = Impey | first5 = S | last6 = Beavo | first6 = JA | last7 = Storm | first7 = DR | year = 1998 | title = Phosphorylation and inhibition of olfactory adenylyl cyclase by CaM kinase II in Neurons: a mechanism for attenuation of olfactory signals | journal = Neuron | volume = 21 | issue = 3| pages = 495–504 | doi=10.1016/s0896-6273(00)80561-9 | pmid=9768837| s2cid = 9860137 | doi-access = free }}</ref> CaMKII will also activate [[phosphodiesterase]], which will then hydrolyze cAMP.<ref>{{cite journal | last1 = Yan | first1 = C | last2 = Zhao | first2 = AZ | last3 = Bentley | first3 = JK | last4 = Loughney | first4 = K | last5 = Ferguson | first5 = K | last6 = Beavo | first6 = JA | year = 1995 | title = Molecular cloning and characterization of a calmodulin-dependent phosphodiesterase enriched in olfactory sensory neurons | journal = Proc Natl Acad Sci USA | volume = 92 | issue = 21| pages = 9677–9681 | doi=10.1073/pnas.92.21.9677| pmid = 7568196 | pmc = 40865 | bibcode = 1995PNAS...92.9677Y | doi-access = free }}</ref> The effect of this negative feedback response inhibits the neuron from further activation when another odor molecule is introduced.