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weight gain relative to controls, LRAT KO mice did not display any
of these signs after eight weeks on the VAD diet. LRAT KO mice
on the VAD diet for 19 weeks showed a relative weight loss in the
latter part of the study. Olfactory tissue was collected from mice in
Study 2, and immunoblots were prepared and probed with an
antibody directed against olfactory marker protein (OMP), a marker
for mature ORNs. Chemiluminescent detection and a BioImaging
System were used to evaluate relative OMP protein expression
levels in LRAT KO VAD, LRAT KO VAS, and WT mice olfactory
tissue cytosolic lysates. Results indicate a modest reduction in
OMP expression in the LRAT VAD, but not LRAT VAS olfactory
tissue relative to WT controls. Our data to date suggest that
VAD may have different and/or less pronounced effects on mice
than rats. Acknowledgements: NIH/NIGMS/MBRS/SCORE
S06 GM 008092
#P92
POSTER SESSION III:
OLFACTION DEVELOPMENT & CNS;
HUMAN PSYCHOPHYSICS; TASTE PERIPHERY
Naris Occlusion Effects Turbinate Development
Elke Weiler
1
, Johannes Seeger
1
, David Coppola
2
1
University of Leipzig, Faculty of Veterinary Medicine, Center of
Pathology and Anatomy, Institute of Veterinary-Anatomy Leipzig,
Germany,
2
Randolph-Macon College/Department of Biology
Ashland, VA, USA
Naris occlusion is the method of choice for investigating the effects
of odor deprivation in mammals. However, unilateral closure of a
naris causes marked changes in the airflow in both the occluded
and open nasal cavity. While on the occluded side the airflow is
dramatically reduced, the open side is forced to carry a larger than
normal volume. Also, naris occlusion abrogates alternating cycles
of breathing, forcing constant duty on the open side. We were
interested if these changes in airflow effect development of nasal
turbinates given that mechanical stress induces bone growth and
turbinates express odorant receptors in regionally defined areas.
We therefore investigated mice aged 18-25 days, that had been
naris occluded or shame operated on the day of birth. Turbinate
morphology was examined in coronal serial sections throughout the
rostrocaudal extent of the nasal cavity. Results demonstrate that
naris occlusion has signficant effects on the size, shape, and
position of nasal turbinates, especially rostrally. The most anterior
turbinate, endoturbinate-I, takes on a delicate “filigree” appearance
on the occluded side relative to the open side: 24% decrease in
area/perimeter (open 65.2, closed 52.6; control 59.5 sq µm/µm;
p<0.005) despite same perimeter; 82% increase in length/width,
(open 7.4; closed 13.5; control 7.9 µm/µm; p <0.001). That these
effects are attributed to airflow is supported by the intermediate
values of controls. We conclude that a stimulus from airflow:
mechanical, thermal or chemical, causes changes in the ontogenesis
of nasal turbinate structure which in turn might induce changes in
expression of odorant receptors. Acknowledgements: This study
was supported by National Science Foundation grant #0641433
to DC
#P93
POSTER SESSION III:
OLFACTION DEVELOPMENT & CNS;
HUMAN PSYCHOPHYSICS; TASTE PERIPHERY
Protein Tyrosine Phosphatase Expression in the Main Olfactory
Epithelium and Olfactory Bulb
Melissa C. Johnson, Carlos A. Cano, Tanielle L. Brew,
Kim Loberbaum, Heidi Lilley
Department of Biology, University of West Georgia
Carrollton, GA, USA
Insulin regulates the outward current flow of the voltage-gated
potassium channel Kv1.3 expressed in mitral cells of the olfactory
bulb (OB). This regulation is due to the protein tyrosine kinase
activity of the insulin receptor, which phosphorylates Kv1.3.
Protein phosphorylation is a common molecular switch that
modifies activities of cellular proteins. However, the cell must also
have a mechanism for turning the switch off. This is accomplished
by activation of protein tyrosine phosphatases that dephosphorylate
proteins. There are numerous studies analyzing the expression and
activity of kinases in the olfactory system, but few studies address
the phosphatase portion of the signaling pathway. The objective
of this study was to analyze the olfactory system expression of
protein tyrosine phosphatase, Src-homology domain containing
phosphatase-2 (SHP-2), which is known to be involved in the
insulin signaling pathway. Cryosections of the OB and main
olfactory epithelium (MOE) of mice were utilized in
immunohistochemical assays to confirm the expression of SHP-2
in these tissues. Photomicrographs of labeled mouse specimens
demonstrate that SHP-2 is expressed in the mitral cell layer,
granule cell layer, and the periglomerular cells of the OB and the
olfactory sensory neuron layer of the MOE. Western blot analysis
of OB tissue indicates that SHP-2 and Kv1.3 form a protein-protein
complex in OB neurons. Parallel experiments using transiently
transfected Human Embryonic Kidney cells (HEK293) indicate
that SHP-2 co-expression attenuates the insulin-induced
phosphorylation of Kv1.3, predicting that the insulin-induced
modulation of Kv1.3 current in mitral cells may be counterbalanced
by SHP-2. Acknowledgements: This work was supported by NIH
DC011923 and Student Research Assistant Program from
University of West Georgia.
#P94
POSTER SESSION III:
OLFACTION DEVELOPMENT & CNS;
HUMAN PSYCHOPHYSICS; TASTE PERIPHERY
Defective Olfactory Sensory Neuron Targeting After Nerve
Injury in Proteolipid Protein Null Mice
Elizabeth Gould, Ernesto Salecedo, Wendy Macklin,
Diego Restrepo
Universty of Colorado School of Medicine Denver, CO, USA
Olfactory sensory neurons (OSNs) are replaced throughout life in a
remarkable regenerative process. New OSNs extend axons from the
olfactory epithelium to the bulb and target one specific ovoid
structure, or glomerulus, depending on which particular olfactory
receptor the neuron expresses. The topological organization is
essential to the processing of olfactory information and is
maintained despite continuous regeneration. Following olfactory
nerve transection in mice, the OSNs regenerate, but injury can
disrupt the organization. Altered rewiring of the olfactory system
may underlie olfactory disturbances after injury in humans.
Therefore, it is important to understand the mechanisms underlying
the regenerative process after injury. Evidence suggests that OSN
axon regeneration is supported by olfactory ensheathing cells
58 | AChemS Abstracts 2012
Abstracts are printed as submitted by the author(s)
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