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151.
Duffell S  Lock EA 《Neurotoxicology》2004,25(6):1031-1040
Previous studies have shown that L-2-chloropropionic acid (L-CPA) produces necrosis to cerebellar granule cells with some associated Purkinje cell damage in the rat. We have re-evaluated the neuropathology using the original sections and fresh sections from archived brain material from rats treated with L-CPA at different ages, times after dosing and the following prior treatment with the N-methyl-D-aspartate (NMDA) receptor antagonist, MK-801. In addition we have determined the lobular distribution of cerebellar granule cell necrosis produced by L-CPA. Using Fluoro-Jade staining to detect degenerating neurons, we have identified three new brain regions that show neuronal cell necrosis as a result of exposure to L-CPA, these are the medial habenular nucleus, pontine gray and inferior olivary nucleus. The neuronal cell degeneration was confirmed in conventional haematoxylin and eosin stained sections and in some cases by glial fibrillary acidic protein staining for reactive gliosis. The neuronal cell necrosis at these new sites was both time and dose dependent; young 22-day-old rats, which are refractory to L-CPA-induced cerebellar granule cell necrosis, did however show some neuronal cell degeneration in the medial habenular, pontine gray and inferior olivary nuclei. Treatment of rats with MK-801 30 min prior to L-CPA, afforded complete protection against the neuronal cell injury in the medial habenular, pontine gray and inferior olivary nuclei, similar to that previously reported for the cerebellum, supporting an excitotoxic mechanism of neuronal cell death. In the cerebellum the lobular distribution of the granule cell loss was not uniform, more severe granule cell loss occurring in lobules 1-4 and 9a + b. This localization exactly mirrors that seen previously in the cerebellum of rats given L-CPA and examined by magnetic resonance imaging (MRI). The basis for the neuronal cell loss in the medial habenular nucleus, pontine gray and inferior olivary nucleus, in addition to the major site in the cerebellum, and the sensitivity of particular cerebellar lobes is not currently understood. Anatomical connections between the sites of injury and their likely neurotransmitter use are discussed.  相似文献   
152.
Nitric oxide (NO) is a diffusible, multifunctional signaling molecule found in many areas of the brain. NO signaling is involved in a wide array of neurophysiological functions including synaptogenesis, modulation of neurotransmitter release, synaptic plasticity, central nervous system blood flow and cell death. NO synthase (NOS) activity regulates the production of NO and the cerebellum expresses high levels of nitric oxide synthase (NOS) in granule, stellate and basket cells. Cerebellar mutant mice provide excellent opportunities to study changes of NO/NOS concentrations and activities to gain a greater understanding of the roles of NO and NOS in cerebellar function. Here, we have reviewed the current understanding of the functional roles of NO and NOS in the cerebellum and present NO/NOS activities that have been described in various cerebellar mutant mice and NOS knockout mice. NO appears to exert neuroprotective effects at low to moderate concentrations, whereas NO becomes neurotoxic as the concentration increases. Excessive NO production can cause oxidative stress to neurons, ultimately impairing neuronal function and result in neuronal cell death. Based on their genetics and cerebellar histopathology, some of cerebellar mutant mice display similarities with human neurological conditions and may prove to be valuable models to study several human neurological disorders, such as autism and schizophrenia.  相似文献   
153.
目的:研究黄角颗粒对脑缺血再灌注损伤大鼠JAK2/STAT3信号通路的影响。方法:采用线栓法构建大鼠脑缺血再灌注损伤模型,取30只健康雄性SD大鼠随机分为假手术组、模型组和黄角颗粒组,并按分组给予相应处理。采用Zea Longa评分法对各组大鼠进行神经功能评分,TTC染色检测各组大鼠脑梗死体积百分比,HE染色观察各组大鼠脑组织病理形态,TUNEL染色法检测各组大鼠脑细胞凋亡率,Western blot检测各组大鼠脑组织中p-JAK2和p-STAT3的蛋白水平。结果:与假手术组相比,模型组大鼠的神经功能缺损程度和神经细胞损伤程度明显加重(P0.05);脑梗死体积百分比和脑细胞凋亡率显著上升(P0.05);脑组织中p-JAK2和p-STAT3的蛋白水平显著上调(P0.05)。与模型组相比,黄角颗粒组大鼠的神经功能缺损程度和神经细胞损伤程度明显减轻(P0.05);脑梗死体积百分比和脑细胞凋亡率显著下降(P0.05);脑组织中p-JAK2和p-STAT3的蛋白水平显著下调(P0.05)。结论:黄角颗粒对脑缺血再灌注损伤大鼠的保护作用可能与抑制JAK2/STAT3信号通路的激活相关。  相似文献   
154.
目的:优选白金妇安颗粒中白芍和柴胡的提取工艺.方法:以HPLC测定芍药苷提取量,分光光度法测定的柴胡总皂苷提取量,采用单因素试验法优选提取溶剂,正交试验法对白金妇安颗粒提取工艺条件进行优选.结果:以70%乙醇为溶剂时芍药苷苷提取量最多,乙醇体积分数>50%时,柴胡总皂昔提取量基本不变;优选提取工艺白芍、柴胡粉碎成粗粉,分别加8,6倍量70%乙醇回流提取2次,每次2h.结论:优选工艺合理,有效成分提取率高.  相似文献   
155.
健胃舒颗粒分煎与合煎的临床观察及实验研究   总被引:1,自引:0,他引:1       下载免费PDF全文
目的:观察中药颗粒分煎与合煎是否存在疗效、药效不同差异。方法:采用自拟复方健胃舒颗粒治疗脾虚肝郁型功能性消化不良患者100例,分为分煎组与合煎组各50例,对比观察两组临床疗效及药效。结果:两组临床治愈率分别为72%和70%,总有效率均为96%,差异无显著性(P>0.05);并且两组在抑制大鼠胃酸、胃蛋白酶活性,调节小鼠胃功能,促进小肠推进度及镇痛药理实验中差异无显著性(P>0.05)。结论:健胃舒颗粒分煎及合煎疗效、药效保持一致,从一个侧面为单味中药浓缩颗粒在临床辨证施治中,灵活配方及加减应用,提供科学依据。  相似文献   
156.
This report concerns an immunohistochemical investigation on RNA-related proteins in the basophilic inclusions (BIs) from patients with adult-onset atypical motor neuron disease. Formalin-fixed, paraffin-embedded sections of the motor cortex and the lumbar spinal cord were examined. The BIs appeared blue in color with H&E and Nissl stain, and pink with methylgreen-pyronin stain. Ribonuclease pretreatment abolished the methylgreen-pyronin staining, suggesting that the BIs contained RNA. Immunohistochemically, the BIs were distinctly labeled with the antibodies against poly(A)-binding protein 1, T cell intracellular antigen 1, and ribosomal protein S6. These proteins are essential constituents of stress granules. In contrast, the BIs were not immunoreactive for ribosomal protein L28 and decapping enzyme 1, which are core components of transport ribonucleoprotein particles and processing bodies, respectively. Moreover, the BIs were not immunopositive for TDP-43. Our results imply that translation attenuation could be involved in the processes of BI formation in this disorder.  相似文献   
157.
慢性脑供血不足的内皮功能变化及药物干预的影响   总被引:2,自引:0,他引:2  
目的探讨慢性脑供血不足(CCCI)的发病机制和病理过程及药物干预对内皮功能的影响。方法根据日本2000年修订的CCCI诊断标准选择研究对象90例,将其分为基础治疗组(A组)、养血清脑颗粒组(B组)、联合用药组(C组)各30例,同时选正常对照组(D组)27例,用药前后测定血清一氧化氮(NO)、血管内皮素-1(ET-1)水平,检测血管内皮功能,并进行统计学分析。结果A、B、C组治疗前分别与D组比较,NO水平降低,ET-1水平升高,差异有统计学意义(P均<0.01);A组治疗前后比较,血清NO、ET-1水平及内皮依赖性血管舒张功能(EDD)差异均无统计学意义,而B、C 2组治疗后各指标水平均较治疗前有改善(P<0.01),非内皮依赖性血管舒张功能(NEDD)在A、B、C 3组治疗前后无差异;治疗后B、C 2组各指标比较差异均无统计学意义,但分别与A组比较,除NEDD(P>0.05)外其他各指标差异均有统计学意义(P<0.01)。结论CCCI患者存在内皮功能异常,而养血清脑颗粒能够调节血管活性物质水平,改善EDD。  相似文献   
158.
To probe the effect of glutamine and GABA on metabolism of [U-(13)C]glutamate, cerebellar astrocytes were incubated with [U-(13)C]glutamate (0.5 mM) in the presence and absence of glutamine (2.5 mM) or GABA (0.2 mM). It could be shown that consumption of [U-(13)C]glutamate was decreased in the presence of glutamine and release of labeled aspartate and [1,2,3-(13)C]glutamate decreased as well, whereas the concentrations of these metabolites increased inside the cells. Glutamine decreased energy production from [U-(13)C]glutamate presumably by substituting for glutamate as an energy substrate. No additional effect was seen in the presence of both glutamine and GABA. When cerebellar granule neurons were incubated with [U-(13)C]glutamate (0.25 mM) and GABA (0.05 mM), less [U-(13)C]glutamate was used for energy production than in controls. Because the barbiturate thiopental did not elicit such response (Qu et al., 2000, Neurochem Int 37:207-215) it appears that GABA also has a metabolic function in the glutamatergic cerebellar granule neurons in contrast to the astrocytes.  相似文献   
159.
目的 建立测定肉桂配方颗粒中桂皮醛和肉桂酸含量的方法.方法 采用HPLC法,色谱柱为Hydrosphere C_(18)(250mm×4.6 mn,5 μm),流动相为乙腈-水-0.1%磷酸溶液(35:25:40),流速为1.0 mL·min~(-1),检测波长为287 nm.结果 桂皮醛的线性范围为0.75~7.50μg(r=0.9995),平均回收率为98.2%(RSD=1.61%);肉桂酸的线性范围为0.22~1.32μg(r=0.9992),平均回收率为97.9%(RSD=1.32%).结论 所建方法简便、灵敏、准确,专属性较强,可有效地控制肉桂配方颗粒的质量.  相似文献   
160.
Accumulating evidence indicates that the Notch signaling pathway fulfills important roles in ischemia-stimulated neurogenesis, which may be regarded as an etiological factor in post-stroke depression. Here we explored Notch1 signaling, hippocampal neurogenesis and behavioral responses to chronic unpredicted mild stress (CUMS) in adult ischemic rats. Animals were treated with permanent middle cerebral artery occlusion followed by an 18 day CUMS procedure. Proliferating cells in the hippocampus and their cell fate were investigated on days 19 and 28 after ischemic surgery. Additionally, expression of the Notch1 intracellular domain (NICD) and its downstream targets Hes1 and Hes5 was examined. A sucrose preference test and forced swim test were used to assess behavioral responses. CUMS produced depressive-like behaviors and decreased the number of proliferating cells on day 19 (both p < 0.001), accompanied by a decreased expression of both Hes1 and Hes5 in the hippocampus of ischemic animals (p < 0.001). On day 28, CUMS resulted in a decreased number of neurogenically-differentiating cells in the subgranular zone (p < 0.001) while permitting differentiation into astrocytes in the hilus (p < 0.05). Hes1 and Hes5 protein expression levels were increased. The expression of the NICD was significantly decreased at both time-points. CUMS led to expression changes in the Notch1 signaling cascade in ischemic rats, most of which concerned hippocampal neurogenesis. This suggests that variation in Notch1 activity and subsequent expression of its downstream targets, including Hes1 and Hes5, may, at least in part, contribute to modulation of ischemia-related hippocampal neurogenesis by CUMS.  相似文献   
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