It is generally considered that olfactory receptors are GTP-binding protein coupled receptors (GCR). There is a possibility that lipids in addition to GCR are also involved in the odor reception. Olfactory receptor potential is induced by activation of cAMP-gated channels, IP-3gated channels or Ca2+ -activated Cl- -channels. In addition, a non-second messenger pathway greatly contributes to generation of in vivo olfactory responses.
