Electrical coupling between olfactory glomeruli.
Neuron
; 67(6): 1034-47, 2010 Sep 23.
Article
in En
| MEDLINE
| ID: mdl-20869599
ABSTRACT
In the Drosophila antennal lobe, excitation can spread between glomerular processing channels. In this study, we investigated the mechanism of lateral excitation. Dual recordings from excitatory local neurons (eLNs) and projection neurons (PNs) showed that eLN-to-PN synapses transmit both hyperpolarization and depolarization, are not diminished by blocking chemical neurotransmission, and are abolished by a gap-junction mutation. This mutation eliminates odor-evoked lateral excitation in PNs and diminishes some PN odor responses. This implies that lateral excitation is mediated by electrical synapses from eLNs onto PNs. In addition, eLNs form synapses onto inhibitory LNs. Eliminating these synapses boosts some PN odor responses and reduces the disinhibitory effect of GABA receptor antagonists on PNs. Thus, eLNs have two opposing effects on PNs, driving both direct excitation and indirect inhibition. We propose that when stimuli are weak, lateral excitation promotes sensitivity, whereas when stimuli are strong, lateral excitation helps recruit inhibitory gain control.
Full text:
1
Collection:
01-internacional
Database:
MEDLINE
Main subject:
Smell
/
Olfactory Receptor Neurons
/
Neuropil
/
Electrical Synapses
Type of study:
Prognostic_studies
Limits:
Animals
Language:
En
Journal:
Neuron
Journal subject:
NEUROLOGIA
Year:
2010
Document type:
Article
Affiliation country:
Estados Unidos