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91.
目的 探究格隆溴铵对高氧诱导幼鼠急性肺损伤(ALI)的影响及作用机制。方法 从30只SD幼鼠中随机选取10只为对照组,其余幼鼠成功复制高氧诱导的ALI模型,随机分为ALI组、格隆溴铵组,每组10只。格隆溴铵组雾化吸入0.8 mg/(kg·d)格隆溴铵,ALI组、对照组吸入等体积生理盐水,连续给药7 d后,测量幼鼠肺组织湿/干重比值(W/D)、肺指数,检测白细胞介素-1β(IL-1β)、白细胞介素-6(IL-6)及肿瘤坏死因子-α(TNF-α)水平及血清活性氧基团(ROS)、超氧化物歧化酶(SOD)水平,比较肺组织病理学变化及Toll样受体4/髓分化因子88(TLR4/MyD88)通路蛋白的表达。结果 与对照组比较,ALI组W/D及肺指数升高(P <0.05),血清IL-1β、IL-6、TNF-α、SOD水平升高(P <0.05),ROS水平降低(P <0.05),TLR4、MyD88蛋白相对表达量上调(P <0.05);与ALI组比较,格隆溴铵组W/D及肺指数降低(P <0.05),血清IL-1β、IL-6、TNF-α、SOD水平降低(P <0.05),ROS水平升高(P <0.05),TLR4、MyD88蛋白相对表达量下调(P <0.05)。结论 格隆溴铵能改善血清炎症指标及氧化应激指标,降低高氧诱导的ALI,其作用机制可能与TLR4/MyD88通路有关。 相似文献
92.
Summary In vivo prostatic secretion was collected from retired breeder Sprague Dawley rats using a method for isolated perfusion of the rat prostatic urethra. Enzymatic acid phosphatase determination was performed on the collected effluent. Control acid phosphatase secretion was 24.2±2.7 nm over 30 minutes. Intravenous phenylephrine 5 mg/kg stimulated a 10 fold increase in acid phosphatase secretion. The secretion seen with phenylephrine was dose dependent and could be blocked with prazosin, but not yohimbine, atropine, or propranolol. Intravenous -adrenergic agonist isoproterenol caused no increase in the secretion of rat prostatic acid phosphatese. Intravenous administration of the cholinergic agonist pilocarpine also resulted in a dose dependent rise in acid phosphatase secretion. The stimulation seen could be blocked by atropine but not phentolamine or propranolol. The stimulation of acid phosphatase secretion seen with 1 adrenergic or cholinergic agonists was not additive. Intravenous vasoactive intestinal peptide did not stimulate acid phosphatase secretion nor did it augment the secretion induced by 1 adrenergic or cholinergic agonists. Release of acid phosphatase into rat prostatic exocrine secretion is under both 1 adrenergic and cholinergic control.Supported by the US Veterans Administration 相似文献
93.
Carlos A. Taira Maria Amelia Enero 《Naunyn-Schmiedeberg's archives of pharmacology》1989,339(5):522-527
Summary Clonidine (3–30 g · kg–1, i.v.) induced a fall in mean arterial pressure in rats after sinoaortic denervation but not in sham-operated animals. Moreover, sinoaortic denervation reduced the bradycardic action of this antihypertensive drug. Pressor and tachycardic response to physostigmine (60 g · kg–1, i.v.) were greater in denervated than in sham-operated rats. The increase of mean arterial pressure was 26.2 ± 2.2 mm Hg in sham-operated rats (n = 12) and 53.8 ± 2.0 mm Hg in denervated rats (n = 12, P < 0.005).Pretreatment with 3 g · kg–1 (i. v.) of clonidine did not alter the pressor response to physostigmine (60 g · kg–1) in either of the two groups; 10 and 30 g · kg–1 of clonidine reduced the physostigmine-induced increase of mean arterial pressure in sham-operated rats but enhanced the pressor response in denervated animals. Furthermore, an ineffective dose of physostigmine (30 g - kg–1 i.v.) induced a pressor response after pretreatment with clonidine (10 gg · kg–1) in denervated rats.Clonidine (10 g · kg–1) did not affect the pressor effect of 1,1 dimethyl-4-phenylpiperazinium iodide (DMPP: 50 g · kg–1 i.v.) or phenylephrine (4 g · kg –1, i.v.) in either group.The anticholinergic effect of clonidine in sham-operated rats may be explained by an inhibitory action on the release of acetylcholine in several brain structures but the facilitatory effect of clonidine observed in denervated animals is not clear. The results did not suggest a peripheral involvement in this facilitatory effect.
Send offprint requests to M. A. Enero at the above address 相似文献
94.
Fluphenazine decanoate (25 mg/kg IM every 3 weeks x 6) resulted in spontaneous vacuous chewing mouth movements and jaw tremor in male Sprague-Dawley rats. These movements could be suppressed by the selective D1 or D2 dopamine antagonists SCH 23390 (0.5 mg/kg) and raclopride (0.5 mg/kg), respectively, and by CCK-8S (50 g/kg). Fluphenazine-induced mouth movements were unaffected by the selective CCK antagonist MK-329, and by a dose of physostigmine (50 g/kg) sufficient to stimulate mouth movements in placebo treated rats. Scopolamine (0.1 mg/kg) suppressed spontaneous mouth movements in placebo-treated rats, but the effect on fluphenazine-induced mouth movements was not significant. A higher dose of scopolamine (0.5 mg/kg) did suppress the neuroleptic-induced mouth movements, but also induced hyperactivity, characterized by increased sniffing and grooming. These findings indicate that mouth movements resulting from the chronic administration of neuroleptics to the rat may serve as a useful pharmacological model of tardive dyskinesia in the human, and suggest that a relative increase of D1 activity as well as impaired CCK function may contribute to the pathogenesis of this disorder. 相似文献
95.
蜥蜴中脑神经通路和起源细胞的形态 总被引:1,自引:0,他引:1
本文采用 HRP 法研究了蛤蚧(Gekko gekko)和鳄蜥(Shinisaurus crocodilurus)视顶盖、中脑深核(NPM)与峡核之间的通路和起源细胞的形态。结果指出:1.顶盖与峡核大细胞部(Imc)呈相互区域对应投射;2.同侧顶盖—Imc 投射细胞主要位于第7层,系有径向树突的梨形细胞;同侧 Imc—顶盖投射细胞为小树突域的梨形或多角形细胞;3.顶盖注射标记的 NPM细胞呈纺锤形,染色浅;峡核注射标记的 NPM 细胞,其粗树突往往伸向顶盖;4.NPM 注射标记顶盖细胞和峡核细胞,前者主要位于顶盖第7层,后者散布在峡核大细胞部(Imc)和峡核小细胞部(Ipc)内。 相似文献
96.
Polyglutamine diseases consist of a group of familial neurodegenerative disorders caused by expression of proteins containing expanded polyglutamine stretch. Over the past several years, tremendous progress has been made in identifying the molecular mechanisms by which the expanded polyglutamine tract leads to neuronal dysfunction and neurodegeneration. A common feature of most polyglutamine disorders is the occurrence of ubiquitin-positive neuronal intranuclear inclusions. The appearance of ubiquitinated aggregates implies an underline incapability of the cellular chaperones and proteasome machinery that normally functions to prevent the accumulation of misfolded proteins. Here we review the recent studies that have revealed a critical role for molecular chaperones and ubiquitin-proteasome pathway in the pathogenesis of polyglutamine diseases. 相似文献
97.
J. S. Kahle C. W. Cotman 《Experimental brain research. Experimentelle Hirnforschung. Expérimentation cérébrale》1993,94(1):97-104
Paired-pulse potentiation of the glutamate-mediated excitatory postsynaptic potential (EPSP) recorded in the dentate gyrus molecular layer is thought to be mediated presynaptically. It is known that the activation of adenosine (A1) and GABAB receptors results in the reduction of glutamate release in the dentate molecular layer via presynaptic mechanisms. To examine possible modulatory roles of these receptors on paired-pulse potentiation, we examined the effects of adenosine and baclofen (a GABAB agonist) on paired-pulse potentiation using extracellular recording from the lateral perforant path in rat hippocampal slices maintained in vitro. We compared these effects with those of l--amino-4-phosphonobutyric acid (l-AP4) over a wide range of interstimulus intervals (ISIs). l-AP4 enhanced paired-pulse potentiation over the full range of ISIs tested (40–800 ms), whereas adenosine enhanced paired-pulse potentiation only at ISIs of 40–100 ms. In contrast, baclofen reduced paired-pulse potentiation only at ISIs of 400–800 ms. Furthermore, baclofen increased the amplitude of lateral perforant path field potentials, previously reported to be baclofen-insensitive. These results suggest that paired-pulse potentiation can be modulated through the activation of adenosine and baclofen receptors, indicate that this modulation is dependent on ISI, and show that there are at least two pharmacologically separable components of paired-pulse potentiation in the dentate gyrus. 相似文献
98.
天然免疫系统通常籍模式识别受体识别病原体相关分子模式。取决于感染的性质,模式识别受体通过细胞外 或细胞内途径识别病原体,并传导相应的信号,激活宿主防御应答,消灭入侵病原体。 相似文献
99.
摘除松果体对大鼠学习记忆及基底前脑胆碱能系统的影响 总被引:3,自引:1,他引:3
目的 探讨松果体功能减退对大鼠学习记忆及基底前脑胆碱能系统的影响。方法 选用 3月龄SD大鼠 2 4只 ,随机分为对照组、去松果体组和褪黑素 (MT)组。手术摘除松果体。饲养 1个月后用Morris水迷宫测试学习记忆功能 ,同时用组织化学和免疫组化方法测定海马、前额叶皮质AchE纤维和内侧隔核、斜角带核的ChAT神经元的数量。结果 与对照组比较 ,去松果体组逃避潜伏期明显增加 ,海马、前额叶皮质AchE纤维数量明显减少 ,但内侧隔核、斜角带核的ChAT神经元数量变化不明显。结论 大鼠去松果体可引起大鼠学习记忆能力减弱 ,这可能与基底前脑胆碱能神经元的功能下降有关 相似文献
100.
Mohammad M. Al‐Qattan Fowzan S. Alkuraya 《American journal of medical genetics. Part A》2019,179(2):266-279
Cenani–Lenz (C–L) syndrome is characterized by oligosyndactyly, metacarpal synostosis, phalangeal disorganization, and other variable facial and systemic features. Most cases are caused by homozygous and compound heterozygous missense and splice mutations of the LRP4 gene. Currently, the syndrome carries one OMIM number (212780). However, C–L syndrome‐like phenotypes as well as other syndactyly disorders with or without metacarpal synostosis/phalangeal disorganization are also known to be associated with specific LRP4 mutations, adenomatous polyposis coli (APC) truncating mutations, genomic rearrangements of the GREM1‐FMN1 locus, as well as FMN1 mutations. Surprisingly, patients with C–L syndrome‐like phenotype caused by APC truncating mutations have no polyposis despite the increased levels of β catenin. The LRP4 and APC proteins act on the WNT (wingless‐type integration site family) canonical pathway, whereas the GREM‐1 and FMN1 proteins act on the bone morphogenetic protein (BMP) pathway. In this review, we discuss the different mutations associated with C–L syndrome, classify its clinical features, review familial adenomatous polyposis caused by truncating APC mutations and compare these mutations to the splicing APC mutation associated with syndactyly, and finally, explore the pathophysiology through a review of the cross talks between the WNT canonical and the BMP antagonistic pathways. 相似文献