Brain stroke is considered as one of the three diseases that threaten human health all over the world. Hypertension and cerebral arteriosclerosis are thought to be the most dangerous risk factors of brain stroke, and they frequently occur together, leading to ischemia of brain tissue. Unfortunately, it is not clear whether the pathological changes resulting from hypertension are related to those resulting from cerebral arteriosclerosis. There have been no ideal animal models mimicking the pathological changes in such a combined condition. In this thesis, an animal model of hypertension combined with cerebral arteriosclerosis in rats was established by occlusion of both the left and right common carotid arteries in spontaneous hypertension rats. Pien Tze Huang (PTH), a reputed traditional Chinese medicinal complex, contains Radix notoginseng, snake bile, calculus bovis, and musk and some other components that are known to protect vessels and cells from injuries. Since different tissue injuries share many common cellular mechanisms, the protection by PTH to in nerves and the circulation systems may also be benefical to cerebrovascular conditions as well. In present experiments, PTH was used to treat hypertension rats that also developed chronic brain ischemia as a result of the bilateral carotid occlusion, and its protective role for neurons and blood vessels was investiaged. / From the data above, more severe damage could be caused by hypertension combined with chronic ischemia. The model of SHR with bilaterally occluded common carotid artery can be used to study pathological changes resulted from hypertension combined with chronic ischemia. PTH was able to protect neurons in stroke. / In the initial part of the work, patients from clinics in two cities in South and North China were compared and analysed; they had been suffering from brain ischemic stroke. About two thirds of the stroke patients were found to have hypertension before the onset of stroke. Their prognosis was significantly worse than those stroke patients without hypertension. In the hypertensive rats with occluded arteries, mean of functional magnetic resonance imaging (fMRI) examination showed that brain blood flow was very weak or even transiently became undetectable at the beginning of the acute stage of brain ischemia, but was restored one hour after the occlusion surgery. In addition, pathological changes in brains of hypertensive rats with induced brain ischemia (carotid occlusion) were examined by Nissl staining, TUNEL staining, cell death ELISA and anti-oxidation enzymes. At day 15 after ischemia, a large number of pyramid cells in the hippocampus of SHR were lost and a great deal of apoptotic cells were found in the CA1 of the hippocampus, while activities of some enzyme including superoxide dismutase (SOD), catalase (CAT), glutathione peroxidase (GPx) were increased. At day 30 and 60, some degenerative changes appeared to have subsided and the cells appeared morphologically normal. The activities of the above enzymes were also decreased at day 60. In WKY control rats with normal blood pressure, neurons in the CA1 were found less damaged after the bilateral carotid occlusion. It was found that apoptotic and dead cells were significantly reduced in rats with hypertension combined with chronic brain ischemia if they had been pre-treated with PTH. Moreover, brain stroke damage was less severe in this pretreated rats. / Zhang, Lihong. / "March 2010." / Adviser: WH Kwong. / Source: Dissertation Abstracts International, Volume: 72-01, Section: B, page: . / Thesis (Ph.D.)--Chinese University of Hong Kong, 2010. / Includes bibliographical references (leaves 116-134). / Electronic reproduction. Hong Kong : Chinese University of Hong Kong, [2012] System requirements: Adobe Acrobat Reader. Available via World Wide Web. / Electronic reproduction. Ann Arbor, MI : ProQuest Information and Learning Company, [200-] System requirements: Adobe Acrobat Reader. Available via World Wide Web. / Abstract also in Chinese.
| Identifer | oai:union.ndltd.org:cuhk.edu.hk/oai:cuhk-dr:cuhk_344446 |
| Date | January 2010 |
| Contributors | Zhang, Lihong., Chinese University of Hong Kong Graduate School. Division of Anatomy. |
| Source Sets | The Chinese University of Hong Kong |
| Language | English, Chinese |
| Detected Language | English |
| Type | Text, theses |
| Format | electronic resource, microform, microfiche, 1 online resource (xix, 134 leaves : ill.) |
| Coverage | China, China |
| Rights | Use of this resource is governed by the terms and conditions of the Creative Commons “Attribution-NonCommercial-NoDerivatives 4.0 International” License (http://creativecommons.org/licenses/by-nc-nd/4.0/) |
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