-transparent.png){kind=logo}
Transduction mechanisms were investigated in human olfactory neurons by determining characteristics of odorant-induced changes in intracellular calcium concentration ([Ca2+]i). Olfactory neurons were freshly isolated from nasal biopsies, allowed to attach to coverslips, and loaded with the calcium-sensitive indicator fura-2. Changes in [Ca2+]i were studied in response to exposure to individual odors, or odorant mixtures composed to distinguish between transduction pathways mediated by adenosine 3'5'-monophosphate (cAMP; mix A) or inositol 1,4,5-trisphosphate (InsP3; mix B). Overall, 52% of biopsies produced one or more odorant-responsive olfactory neurons, whereas 24% of all olfactory neurons tested responded to odorant exposure with a change in [Ca2+]i. As in olfactory neurons from other species, the data suggest that odorant exposure elicited calcium influx via second-messenger pathways involving cAMP or InsP3. Unlike olfactory neurons from other species that have been tested, some human olfactory neurons responded to odorants with decreases in [Ca2+]i. Also in contrast with olfactory neurons from other species, human olfactory neurons were better able to discriminate between odorant mixtures in that no neuron responded to more than one type of odor or mixture. These results suggest the presence of a previously unreported type of olfactory transduction mechanism, and raise the possibility that coding of odor qualities in humans may be accomplished to some degree differently than in other vertebrates, with the olfactory neuron itself making a greater contribution to the discrimination process.
N E Rawson, and
G Gomez, and
B Cowart, and
J G Brand, and
L D Lowry, and
E A Pribitkin, and
D Restrepo
August 2007,
The Journal of neuroscience : the official journal of the Society for Neuroscience,
N E Rawson, and
G Gomez, and
B Cowart, and
J G Brand, and
L D Lowry, and
E A Pribitkin, and
D Restrepo
August 1972,
Tsitologiia,
N E Rawson, and
G Gomez, and
B Cowart, and
J G Brand, and
L D Lowry, and
E A Pribitkin, and
D Restrepo
February 2004,
The Journal of general physiology,
N E Rawson, and
G Gomez, and
B Cowart, and
J G Brand, and
L D Lowry, and
E A Pribitkin, and
D Restrepo
January 2011,
Proceedings of the National Academy of Sciences of the United States of America,
N E Rawson, and
G Gomez, and
B Cowart, and
J G Brand, and
L D Lowry, and
E A Pribitkin, and
D Restrepo
August 2005,
The Journal of neuroscience : the official journal of the Society for Neuroscience,
N E Rawson, and
G Gomez, and
B Cowart, and
J G Brand, and
L D Lowry, and
E A Pribitkin, and
D Restrepo
August 1972,
The Journal of general physiology,
N E Rawson, and
G Gomez, and
B Cowart, and
J G Brand, and
L D Lowry, and
E A Pribitkin, and
D Restrepo
January 1981,
Brain research bulletin,
N E Rawson, and
G Gomez, and
B Cowart, and
J G Brand, and
L D Lowry, and
E A Pribitkin, and
D Restrepo
June 2005,
Science (New York, N.Y.),
N E Rawson, and
G Gomez, and
B Cowart, and
J G Brand, and
L D Lowry, and
E A Pribitkin, and
D Restrepo
June 1998,
The Journal of neuroscience : the official journal of the Society for Neuroscience,
N E Rawson, and
G Gomez, and
B Cowart, and
J G Brand, and
L D Lowry, and
E A Pribitkin, and
D Restrepo
June 1999,
Science (New York, N.Y.),
