The current work explores the behavioural and anatomical consequences of
unilateral neonatal bulbectomy (OBX) in male and female rats at postnatal day 1 (PI) and
P10. In adulthood the animals underwent a battery of motor and cognitive tests, and
diffuse effects of early brain injury on the development of behavior were found.
Disturbing olfactory sense input during development affected motor output. Rats
normally display an equal distribution of right or left paw preference. In this study, both
OBX sexes showed a shifted paw preference to the ipsilesional side, and forelimb deficits
were found in a skilled reaching task. Lesion animals also showed enhanced
performance on a visually driven spatial cognitive test. Cross-modal compensatory
changes may be responsible. Morphological changes within the cerebral cortex are
described, including bulbar changes, enlarged but fewer glomeruli, smaller accessory
olfactory bulb, decreased downstream connectivity, and a rostral shift of the forebrain
toward the olfactory bulb. Changes to the lateral cortex were found in both intact and
lesion hemispheres, along with dendritic changes in the forelimb reaching area. Cellular
regeneration within the lesion bulb was indicated. Changed shape and relative size
increases compared to the intact bulb were found. BrdU labeling showed increased
mitotic activity in P10 lesion animals. These findings demonstrate that the impact of
olfactory injury during early development goes well beyond odor perception and
discrimination, and that olfactory inputs during development significantly contribute to
the development of the neocortex. / xix, 195 leaves : ill. (some col.) ; 29 cm.
| Identifer | oai:union.ndltd.org:LACETR/oai:collectionscanada.gc.ca:ALU.w.uleth.ca/dspace#10133/683 |
| Date | January 2007 |
| Creators | Goldsbury, Robin Paulette, University of Lethbridge. Faculty of Arts and Science |
| Contributors | Kolb, Bryan |
| Publisher | Lethbridge, Alta. : University of Lethbridge, Faculty of Arts and Science, 2007, Arts and Science, Department of Neuroscience |
| Source Sets | Library and Archives Canada ETDs Repository / Centre d'archives des thèses électroniques de Bibliothèque et Archives Canada |
| Language | en_US |
| Detected Language | English |
| Type | Thesis |
| Relation | Thesis (University of Lethbridge. Faculty of Arts and Science) |
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