Peripheral Odor Coding in the Rat and Frog: Quality and Intensity Specification

In mammals, two recent studies have shown recently that one odor molecule can be recognized by several molecular olfactory receptors (ORs), and a single OR can recognize multiple odor molecules. In addition, one olfactory receptor neuron (ORN) may respond to different stimuli chosen as representativ...

Full description

Saved in:
Bibliographic Details
Published in:The Journal of neuroscience 2000-03, Vol.20 (6), p.2383-2390
Main Authors: Duchamp-Viret, Patricia, Duchamp, Andre, Chaput, Michel A
Format: Article
Language:English
Subjects:
Action Potentials - physiology
Animals
Anura
Discrimination Learning - physiology
Electrophysiology
Odorants
Olfactory Receptor Neurons - chemistry
Olfactory Receptor Neurons - physiology
Rana
Rats
Rats, Wistar
Receptors, Odorant - physiology
Smell - physiology
Species Specificity
Stimulation, Chemical
Citations: Items that this one cites
Items that cite this one
Online Access:Get full text
Tags: Add Tag
No Tags, Be the first to tag this record!
Description
Summary:In mammals, two recent studies have shown recently that one odor molecule can be recognized by several molecular olfactory receptors (ORs), and a single OR can recognize multiple odor molecules. In addition, one olfactory receptor neuron (ORN) may respond to different stimuli chosen as representative of distinct odor qualities. The aim of the present study was to analyze quality and intensity coding abilities of rat single ORNs, comparing them with previous extensive data gathered in the frog to get insight into the generality of olfactory coding mechanisms over vertebrates. Response properties of 90 rat ORNs to different odors or to one odor at different concentrations were analyzed. In the rat and the frog, odor quality appears to be specified through the identity of activated ORNs. However, rat ORNs have higher response thresholds. This lower sensitivity may be interpreted as an increase in selectivity of rat ORNs for low or medium odor intensities. In these conditions, the lower proportion of activated ORNs could be counterbalanced by their number, as well as by their higher glomerular convergence ratio in the olfactory bulb. From amphibians to mammals, the olfactory system appears to use universal mechanisms based on a combinatorial-coding mode that may allow quasi-infinite possibilities of adaptation to various olfactory environments.
ISSN:0270-6474
1529-2401
DOI:10.1523/jneurosci.20-06-02383.2000