REGULATION OF THE INHIBITORY DRIVE IN THE OLFACTORY BULB

Simple item page
dc.contributor.advisorAraneda, Ricardo Cen_US
dc.contributor.authorNunez-Parra, Alexia Franciscaen_US
dc.contributor.departmentNeuroscience and Cognitive Scienceen_US
dc.contributor.publisherDigital Repository at the University of Marylanden_US
dc.contributor.publisherUniversity of Maryland (College Park, Md.)en_US
dc.date.accessioned2013-06-28T06:51:53Z
dc.date.available2013-06-28T06:51:53Z
dc.date.issued2013en_US
dc.description.abstractAnimals are exposed to a variety of odor cues that serve as environmental guides for their exploratory and social behaviors. Two distinct but complementing pathways process chemosensory cues: the Main and the Accessory olfactory System (AOS). Sensory neurons send their axons to the olfactory bulb (OB), specifically to the main and the accessory olfactory bulb (MOB and AOB, respectively) where they synapse onto principal neurons, the mitral (MCs). The OB is the only relay center between sensory neurons and cortical and limbic structures and therefore important aspects of odor processing occur in this region. Specifically, a distinctive mechanism used for olfactory processing is a strict regulation of MCs output by inhibitory neurons called granule cells (GCs). Importantely, inhibition of MCs is a dynamic process; it is regulated by the constant addition of new GCs to the OB circuit throughout life, in a process known as adult neurogenesis. Little is known, however, about the contribution of adult born neurons to the processing of olfactory cues, known as pheromones. Detection of pheromones by the AOS is critical for proper display of social behaviors such as hierarchical dominance and mate recognition. Here, we studied how the integration of new-born neurons could be regulated. We found that the arrival of new neurons into the adult AOB increases after animals are exposed to aggression and mate cues, suggesting that these newly arrived neurons can add important plasticity to the AOB circuitry and modify olfactory processing under different behavioral contexts. In addition, GCs mediated inhibition in the OB is precisely controlled by an extensive centrifugal innervation. For example, cortical feedback projections and neuromodulatory afferents originating in the midbrain and basal forebrain excite GC, inhibiting MCs' and decreasing their output. Regulation of of GCs by inhibition has also been reported, however, the source of this inhibition and its relevance to olfactory processing is not known. Here we characterized inhibitory inputs onto GCs and show that GCs receive extensive inhibition from GABAergic neurons in the HDB/MCPO and from neighboring GCs. Moreover, we show, for the first time, that inhibition onto GCs is required for proper olfactory discrimination.en_US
dc.identifier.urihttp://hdl.handle.net/1903/14117
dc.subject.pqcontrolledNeurosciencesen_US
dc.subject.pquncontrolledadult neurogenesisen_US
dc.subject.pquncontrolledchannelrhodopsinen_US
dc.subject.pquncontrolledgranule cellsen_US
dc.subject.pquncontrolledHDBen_US
dc.subject.pquncontrolledinhibitionen_US
dc.subject.pquncontrolledolfactory bulben_US
dc.titleREGULATION OF THE INHIBITORY DRIVE IN THE OLFACTORY BULBen_US
dc.typeDissertationen_US

Files

Original bundle
Now showing 1 - 1 of 1
Thumbnail Image
Name:
NunezParra_umd_0117E_14227.pdf
Size:
3.82 MB
Format:
Adobe Portable Document Format
Download

Collections

UMD Theses and Dissertations
Biology Theses and Dissertations