The spatial representation of odors by olfactory receptor neuron input to the olfactory bulb is concentration invariant

2000 ◽  
Vol 199 (2) ◽  
pp. 162-163 ◽  
Author(s):  
M Wachowiak ◽  
M Zochowski ◽  
LB Cohen ◽  
CX Falk
Keyword(s):  
Olfactory Bulb ◽  
Olfactory Receptor ◽  
Spatial Representation ◽  
Olfactory Receptor Neuron ◽  
Receptor Neuron

scholarly journals Inhibition of Olfactory Receptor Neuron Input to Olfactory Bulb Glomeruli Mediated by Suppression of Presynaptic Calcium Influx

2005 ◽  
Vol 94 (4) ◽  
pp. 2700-2712 ◽  
Author(s):  
Matt Wachowiak ◽  
John P. McGann ◽  
Philip M. Heyward ◽  
Zuoyi Shao ◽  
Adam C. Puche ◽  
...  
Keyword(s):  
Olfactory Bulb ◽  
Olfactory Receptor ◽  
Transmitter Release ◽  
Calcium Influx ◽  
Imaging Techniques ◽  
Olfactory Receptor Neuron ◽  
Olfactory Nerve ◽  
Presynaptic Terminal ◽  
Receptor Neuron ◽  
Paired Pulse

We investigated the cellular mechanism underlying presynaptic regulation of olfactory receptor neuron (ORN) input to the mouse olfactory bulb using optical-imaging techniques that selectively report activity in the ORN presynaptic terminal. First, we loaded ORNs with calcium-sensitive dye and imaged stimulus-evoked calcium influx in a slice preparation. Single olfactory nerve shocks evoked rapid fluorescence increases that were largely blocked by the N-type calcium channel blocker ω-conotoxin GVIA. Paired shocks revealed a long-lasting suppression of calcium influx with ∼40% suppression at 400-ms interstimulus intervals and a recovery time constant of ∼450 ms. Blocking activation of postsynaptic olfactory bulb neurons with APV/CNQX reduced this suppression. The GABAB receptor agonist baclofen inhibited calcium influx, whereas GABAB antagonists reduced paired-pulse suppression without affecting the response to the conditioning pulse. We also imaged transmitter release directly using a mouse line that expresses synaptopHluorin selectively in ORNs. We found that the relationship between calcium influx and transmitter release was superlinear and that paired-pulse suppression of transmitter release was reduced, but not eliminated, by APV/CNQX and GABAB antagonists. These results demonstrate that primary olfactory input to the CNS can be presynaptically regulated by GABAergic interneurons and show that one major intracellular pathway for this regulation is via the suppression of calcium influx through N-type calcium channels in the presynaptic terminal. This mechanism is unique among primary sensory afferents.

Interglomerular Center-Surround Inhibition Shapes Odorant-Evoked Input to the Mouse Olfactory Bulb In Vivo

2006 ◽  
Vol 95 (3) ◽  
pp. 1881-1887 ◽  
Author(s):  
Dejan Vučinić ◽  
Lawrence B. Cohen ◽  
Efstratios K. Kosmidis
Keyword(s):  
Olfactory Bulb ◽  
Olfactory Receptor ◽  
Presynaptic Inhibition ◽  
Granule Cells ◽  
Olfactory Receptor Neuron ◽  
Receptor Neuron ◽  
Surround Inhibition ◽  
Neuron Terminals

Mouse olfactory receptor proteins have relatively broad odorant tuning profiles, so single odorants typically activate a substantial subset of glomeruli in the main olfactory bulb, resulting in stereotyped odorant- and concentration-dependent glomerular input maps. One of the functions of the olfactory bulb may be to reduce the extent of this rather widespread activation before transmitting the information to higher olfactory centers. Two circuits have been studied in vitro that could perform center-surround inhibition in the olfactory bulb, one circuit acting between glomeruli, the other through the classical reciprocal synapses between the lateral dendrites of mitral cells and the dendrites of granule cells. One unanswered question from these in vitro measurements was how these circuits would affect the response to odorants in vivo. We made measurements of the odorant-evoked increase in calcium concentration in the olfactory receptor neuron terminals in the anesthetized mouse to evaluate the role of presynaptic inhibition in reshaping the input to the olfactory bulb. We compared the glomerular responses in 2- to 4-wk-old mice before and after suppressing presynaptic inhibition onto the receptor neuron terminals with the GABAB antagonist, CGP46381 . We find that the input maps are modified by an apparent center-surround inhibition: strongly activated glomeruli appear to suppress the release from receptor neurons terminating in surrounding glomeruli. This form of lateral inhibition has the effect of increasing the contrast of the sensory input map.

scholarly journals Olfactory receptor neuron coding in the turbulent realm

2013 ◽  
Vol 14 (S1) ◽  
Author(s):  
Jean-Baptiste Masson ◽  
Christelle Monsempes ◽  
Jean-Pierre Rospars ◽  
Philippe Lucas
Keyword(s):  
Olfactory Receptor ◽  
Olfactory Receptor Neuron ◽  
Receptor Neuron ◽  
Neuron Coding

scholarly journals Olfactory receptor neuron responses coding for rapid odour sampling

2011 ◽  
Vol 589 (9) ◽  
pp. 2261-2273 ◽  
Author(s):  
Ambarish S. Ghatpande ◽  
Johannes Reisert
Keyword(s):  
Olfactory Receptor ◽  
Olfactory Receptor Neuron ◽  
Receptor Neuron

scholarly journals Dysregulation of Olfactory Receptor Neuron Lineage in Schizophrenia

2001 ◽  
Vol 58 (9) ◽  
pp. 829 ◽  
Author(s):  
Steven E. Arnold ◽  
Li-Ying Han ◽  
Paul J. Moberg ◽  
Bruce I. Turetsky ◽  
Raquel E. Gur ◽  
...  
Keyword(s):  
Olfactory Receptor ◽  
Olfactory Receptor Neuron ◽  
Receptor Neuron
Sign in / Sign up

Export Citation Format

Share Document