碩士 / 國防醫學院 / 生物及解剖學研究所 / 94 / Abstract
CD200 is a type-1 membrane glycoprotein that contains two immuneoglobulin superfamily domains and it functions through interactions with other cell-surface proteins. Up to now, CD200 is concluded as an immunosuppressive molecule. CD200 has broad distribution and present on leucocytes, endothelial cells and some other cell types, in particular on brain cells.
Whether CD200 expressions in the CNS are differential and dependent on specific brain regions or cell types have not yet been determined. Our preliminary data showed that CD200 expressions were significantly differential in the rat hippocampus dependent on specific strata in the cornu ammonis 1 (CA1), CA3 and dentate gyrus. In general, the strata composed of neuropil expressed intense CD200 immunoreactivity and those with compacted neurons were the weakest. Immuno-electron microscopic data further revealed that CD200 was distributed at the cytoplasmic membrane of neurons in a fragmental profile, but the most striking, at the postsynaptic dense plaque. The differential expressions of CD200 were also true in the developing hippocampus that did not display the adult pattern of CD200 until at postnatal days 28. Western blot analysis showed two peaks of CD200 expression during the first month of hippocampal postnatal development. Ultrastructural study showed an existence of CD200 in sequential stages of synapse formation. The developmental revolution and distribution of CD200 in rat hippocampi were less consistent with those of synaptic proteins such as SNAP-25 and PSD-95.
Interestingly, a well colocalization of CD200 with GAP-43 was found in the dentate gyrus of both adult and developing rats, suggesting a CD200 function in
the synaptic integrality rather than synaptogenesis. Using a model of kainite-induced status epileptics that caused degeneration of hippocampal neurons and sprouting of mossy fibers, we observed a significant attenuation of CD200 in the dentate molecular layers of acute epileptic rats. Based on our present data, CD200 involvement in synaptic maintenance and plasticity was therefore suggested.
| Identifer | oai:union.ndltd.org:TW/094NDMC0589008 |
| Date | January 2006 |
| Creators | HSIEH.YU-MING, 謝玉銘 |
| Contributors | WU,CHING-HSIANG, 吳慶祥 |
| Source Sets | National Digital Library of Theses and Dissertations in Taiwan |
| Language | zh-TW |
| Detected Language | English |
| Type | 學位論文 ; thesis |
| Format | 86 |
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