Controversial issues in vertebrate olfactory transduction.
A number of controversial issues in olfactory transduction are discussed including the matter of multiple transduction pathways, with a new experiment proposed. Evidence is reviewed concerning the fact that cyclic AMP is the only pathway mediating olfactory transduction. Two knockout mice have been produced: a knockout for a cyclic nucleotide-gated channel and a G(olf) knockout. The results obtained with both mice are consistent with cyclic AMP being the only second messenger. The evidence for gaseous second channel messengers is also reviewed. Slow gating kinetics of the cyclic nucleotide-gated channel and the detection of single-odorant molecules are reviewed. A new phenomenon in which odorants can block odorant responses is discussed.
Gold
G H
GH
Monell Chemical Senses Center, Philadelphia, Pennsylvania 19104-3308, USA.
D000818:Animals; D000242:Cyclic AMP / Q000378:metabolism; D005740:Gases / Q000378:metabolism; D015640:Ion Channel Gating / Q000502:physiology; D007473:Ion Channels / Q000502:physiology; D009712:Nucleotides, Cyclic / Q000502:physiology; D009812:Odorants; D009833:Olfactory Pathways / Q000502:physiology*; D015290:Second Messenger Systems / Q000502:physiology; D015398:Signal Transduction / Q000502:physiology*; D014714:Vertebrates / Q000502:physiology*
D005740:Gases; D007473:Ion Channels; D009712:Nucleotides, Cyclic; D000242:Cyclic AMP