There are two types of stroke: ischemic and hemorrhagic. Intracerebral hemorrhage (ICH) accounts for about 15% of all strokes and is often severe. Currently no treatments are available to reduce injury, but rehabilitation may improve recovery. Most studies focus on ischemia, putting little emphasis on understanding recovery after hemorrhage.
In chapter 2, we evaluated exercise prior to and/or following ICH. Similar protocols improve recovery after ischemic stroke, and we hypothesized that the treatment would also reduce deficits after hemorrhagic injury. However, exercise was not beneficial for ICH and increased intensity of treatment worsened functional outcome. In chapter 3 we assessed amphetamine and/or rehabilitation after ICH, an intervention also shown to improve recovery after ischemia. The rehabilitation consisted of environmental enrichment (EE) with modest amounts of training on beam and skilled reaching. Rehabilitation but not amphetamine partially improved recovery. Skilled reaching was not improved by rehabilitation so we decided to combine EE with more reach training. In chapter 4, we found that two weeks of rehabilitation (EE and skilled reaching), started one week after ICH significantly reduced lesion volume, and improved recovery on walking and skilled reaching tests. We were particularly interested in the mechanisms contributing to the reduction in lesion volume after ICH, and attempted to identify these.
In chapter 5, we used the same rehabilitation intervention as in chapter 4 to determine if treatment alters dendritic complexity, spine density, or cell proliferation. Unfortunately, the reduction in lesion volume from chapter 4 was not replicated. But we were able to identify several plastic changes. Dendritic complexity was increased in neurons of the forelimb motor cortex ipsilateral to injury. Dendritic complexity of neurons in the peri-hematoma region and corresponding area in the uninjured hemisphere were also increased. In contrast, rehabilitation did not alter spine density or cell proliferation.
In summary, we found that treatments that work for ischemic stroke do not necessarily work for hemorrhagic injury. Some methods of rehabilitation are able to reduce functional deficits and in some cases lesion volume after ICH. These rehabilitation effects are likely due to enhanced plasticity and not cell genesis.
| Identifer | oai:union.ndltd.org:LACETR/oai:collectionscanada.gc.ca:AEU.10048/1414 |
| Date | 11 1900 |
| Creators | Auriat, Angela Michelle |
| Contributors | Colbourne, Fred (Psychology), Treit, Dallas (Psychology), Sturdy, Chris (Psychology), Winship, Ian (Psychiatry), Robbin, Gibb (Neuroscience, University of Lethbridge) |
| Source Sets | Library and Archives Canada ETDs Repository / Centre d'archives des thèses électroniques de Bibliothèque et Archives Canada |
| Language | English |
| Detected Language | English |
| Type | Thesis |
| Format | 6865352 bytes, application/pdf |
| Relation | Auriat, AM., Wowk, S, Colbourne, F, Rehabilitation after intracerebral hemorrhage in rats improves recovery with enhanced dendritic complexity but no effect on cell proliferation. Behav Brain Res. 2010 Dec 6; 214 (1): 42-7, Auriat, AM, Colbourne, F. Delayed rehabilitation lessens brain injury and improves recovery after intracerebral hemorrhaqge in rats. Brain Res. 2009 Jan 28; 1251:262-8., Auriat, AM, Colbourne, F. Influence of amphetamine on recovery after intracerebral hemorrhage in rats. Behav Brain Res. 2008 Jan 25; 186(2) 222-9., Auriat, AM, Grams JD, Yan RH, Colbourne F. Forced exercise does not improve recovery after hemorrhagic stroke in rats. Brain Res. 2006 Sep 13; 1109(1):183-91. |
Page generated in 0.0056 seconds