Odorant identity is represented in the olfactory bulb (OB) by the glomerular activity pattern, which reflects a combination of activated odorant receptors (ORs) in the olfactory epithelium. To elucidate this neuronal circuit at the molecular level, we established a functional OR identification strategy based on glomerular activity by combining in vivo Ca(2+) imaging, retrograde dye labeling, and single-cell RT-PCR. Spatial and functional mapping of OR-defined glomeruli revealed that the glomerular positional relationship varied considerably between individual animals, resulting in different OR maps in the OB. Notably, OR-defined glomeruli exhibited different ligand spectra and far higher sensitivity compared to the in vitro pharmacological properties of corresponding ORs. Moreover, we found that the olfactory mucus was an important factor in the regulation of in vivo odorant responsiveness. Our results provide a methodology to examine in vivo glomerular responses at the receptor level and further help address the long-standing issues of olfactory sensitivity and specificity under physiological conditions.

Download full-text PDF

Source
http://dx.doi.org/10.1016/j.neuron.2006.10.019DOI Listing

Publication Analysis

Top Keywords

olfactory bulb
8
sensitivity specificity
8
glomerular activity
8
ors olfactory
8
or-defined glomeruli
8
olfactory
5
odorant
4
odorant receptor
4
receptor map
4
map mouse
4

Similar Publications

Although animals can reliably locate and recognize odorants embedded in complex environments, the neural circuits for accomplishing these tasks remain incompletely understood. Adaptation is likely to be important as it could allow neurons in a brain area to adjust to the broader sensory environment. Adaptive processes must be flexible enough to allow the brain to make dynamic adjustments, while maintaining sufficient stability so that organisms do not forget important olfactory associations.

View Article and Find Full Text PDF

Hygienic insecticides are applied directly to the living environment and are closely related to human life. Dimefluthrin (DIM) is one of the most widely used hygienic insecticides globally. However, with increasing mosquito resistance, both the concentration and duration of DIM usage have risen, prompting public concerns regarding its neurotoxic risks, especially for immunocompromised children.

View Article and Find Full Text PDF

Regulation of neural stem cells by innervating neurons.

J Neurochem

January 2025

Neurosciences and Mental Health Institute, University of Alberta, Edmonton, Alberta, Canada.

The adult central nervous system (CNS) hosts several niches, in which the neural stem and precursor cells (NPCs) reside. The subventricular zone (SVZ) lines the lateral brain ventricles and the subgranular zone (SGZ) is located in the dentate gyrus of the hippocampus. SVZ and SGZ NPCs replace neurons and glia in the homeostatic as well as diseased or injured states.

View Article and Find Full Text PDF

Compared with their free-ranging counterparts, wild animals in captivity experience different conditions with lasting physiological and behavioural effects. Although shifts in gene expression are expected to occur upstream of these phenotypes, we found no previous gene expression comparisons of captive versus free-ranging mammals. We assessed gene expression profiles of three brain regions (cortex, olfactory bulb and hippocampus) of wild shrews () compared with shrews kept in captivity for two months and undertook sample dropout to examine robustness given limited sample sizes.

View Article and Find Full Text PDF

Ion Channels in Odor Information Processing of Neural Circuits of the Vertebrate Olfactory Bulb.

Int J Mol Sci

December 2024

Department of Anesthesiology, West China Hospital, Sichuan University, Chengdu 610041, China.

Olfactory disorders and their associated complications present a considerable challenge to an individual's quality of life and emotional wellbeing. The current range of treatments, including surgical procedures, pharmacological interventions, and behavioral training, frequently proves ineffective in restoring olfactory function. The olfactory bulb (OB) is essential for odor processing and plays a pivotal role in the development of these disorders.

View Article and Find Full Text PDF

Want AI Summaries of new PubMed Abstracts delivered to your In-box?

Enter search terms and have AI summaries delivered each week - change queries or unsubscribe any time!