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1.
目的 探讨p38丝裂原活化蛋白激酶(p38MAPK)信号转导通路对急性坏死性胰腺炎(ANP)大鼠低钙血症和甲状旁腺激素受体1(PTHR1)表达的影响.方法 将雄性SD大鼠72只按完全随机法分为ANP组、SB203580干预(SB)组和假手术(SO)组,每组分3、6、12 h 3个时间点,每个时间点8只.以5%牛磺脱氧胆酸钠逆行胰胆管注射建立ANP模型,SB组在造模前30 min腹腔注射p38MAPK特异抑制剂SB203580 10 mg/kg体重.观察各组血清钙浓度,蛋白质印迹法(Western blotting)分析骨组织磷酸化p38MAPK(P-p38 MAPK)和TNF-α变化,实时RT-PCR检测骨组织PTHR1 mRNA表达.结果 制模后6 h,SO组、ANP组和SB组血清钙浓度分别为(2.50±0.08)mmoL/L、(2.11±0.06)mmol/L和(2.35±0.10)mmol/L;骨组织P-p38 MAPK表达量分别为0.14±0.04、0.80±0.06和0.33±0.05;骨组织TNF-α表达量分别为0、0.91±0.04和0.44±0.03;骨组织PTHR1 mRNA表达量分别为1.00±0.12、0.23±0.04和0.44±0.06.SB组骨组织P-p38 MAPK及TNF-α表达较ANP组显著降低(P<0.01);骨组织PTHR1 mRNA表达量及血清钙浓度较ANP组显著增加(P<0.01).结论 p38MAPK信号转导通路可介导ANP低钙血症的发生,抑制该通路可改善ANP低钙血症.  相似文献   

2.
目的探讨丝裂原活化蛋白激酶p38(p38MAPK)抑制剂SB203580对重症胰腺炎大鼠急性肺损伤的保护作用。方法健康雄性SD大鼠60只,随机均分为3组:假手术组、重症胰腺炎组(模型组)、p38MAPK抑制剂SB203580+重症胰腺炎组(抑制剂组),12 h后取左肺下叶测组织湿/干重比,用Western印迹法检测右肺上叶环氧合酶(COX)-2、基质金属蛋白酶(MMP)9、诱导型一氧化氮合酶(i NOS)和磷酸化p38(p-p38)蛋白的表达,右肺下叶行病理学观察。结果与假手术组比较,模型组肺组织湿/干重比明显增加(P<0.05),肺组织p-p38、i NOS、MMP9、COX-2蛋白表达明显增高(P<0.05),与模型组比较,抑制剂组肺组织湿/干重比明显降低(P<0.05),p-p38、i NOS、MMP9、COX-2蛋白表达量明显(P<0.05)。结论 P38抑制剂SB203580通过减轻肺组织中p-p38、MMP9、i NOS和COX-2的表达,从而减轻肺组织的损伤。  相似文献   

3.
目的 探讨阿魏酸钠(SF)在抗大鼠脑缺血/再灌注损伤过程中对p38MAPK信号通路的影响.方法 采用线栓法阻塞大鼠大脑中动脉(MCAO)建立大鼠局灶性脑缺血/再灌注损伤模型,大鼠于MCAO前1 h股静脉注射不同剂量SF100 mg/kg、50 mg/kg、20 mg/kg及p38MAPK抑制剂SB203580,观察各组脑缺血再灌注损伤后大鼠神经学评分,TUNEL法检测神经细胞的凋亡及Westernblot检测p38MAPK、p-p38MAPK蛋白表达.结果 假手术组无神经学改变,SF100 mg/kg、50 mg/kg及p38MAPK抑制剂SB203580组神经学评分明显低于缺血再灌注组(P<0.05),各用药组间无明显差异.SF100 mg/kg、50 mg/kg、20 mg/kg及p38MAPK抑制剂SB203580TUNEL阳性细胞率(%)均较缺血再灌注组明显下降.假手术组未见p-p38MAPK表达,缺血再灌注组p-p38MAPK显著增高,SF100 mg/kg、50 mg/kg、20 mg/kg对脑组织总p38MAPK表达影响不明显(P>0.05),主要下调p-p38MAPK表达.结论 阿魏酸钠对大鼠缺血再灌注损伤的保护作用机制可能与抑制p38MAPK信号传导通路有关.  相似文献   

4.
目的建立烟雾暴露的支气管哮喘(简称哮喘)大鼠模型,观察p38有丝分裂原活化蛋白激酶(p38 mitogen-activated protein kinase,p38MAPK)抑制剂SB203580对其的治疗作用。方法将Wistar大鼠随机分为4组,即正常对照组、哮喘组、烟雾暴露的哮喘组及SB203580干预组。动物肺功能仪测定大鼠呼气阻力、吸气阻力及肺顺应性,观察肺组织病理学改变,通过ELISA检测大鼠肺组织中IL-4、IL-5和IL-8的表达。结果与烟雾暴露的哮喘组相比,SB203580干预组大鼠的气道阻力显著下降,肺顺应性显著升高,差异有统计学意义(P<0.05);气道炎症明显减轻;肺组织中IL-4、IL-5和IL-8的含量显著下降,差异有统计学意义(P<0.05)。结论 p38 MAPK抑制剂SB203580可以改善烟雾暴露的哮喘大鼠的气道炎症,减轻其支气管收缩反应。  相似文献   

5.
目的 建立烟雾暴露的支气管哮喘(简称哮喘)大鼠模型,观察p38有丝分裂原活化蛋白激酶(p38 mitogen-activated protein kinase,p38 MAPK)抑制剂SB203580对其的治疗作用.方法 将Wistar大鼠随机分为4组,即正常对照组、哮喘组、烟雾暴露的哮喘组及SB203580干预组.动物肺功能仪测定大鼠呼气阻力、吸气阻力及肺顺应性,观察肺组织病理学改变,通过ELISA检测大鼠肺组织中IL-4、IL-5和IL-8的表达.结果 与烟雾暴露的哮喘组相比,SB203580干预组大鼠的气道阻力显著下降,肺顺应性显著升高,差异有统计学意义(P<0.05);气道炎症明显减轻;肺组织中IL-4、IL-5和IL-8的含量显著下降,差异有统计学意义(P <0.05).结论 p38 MAPK抑制剂SB203580可以改善烟雾暴露的哮喘大鼠的气道炎症,减轻其支气管收缩反应.  相似文献   

6.
目的研究p38丝裂原活化蛋白激酶(p38MAPK)信号通路抑制剂对缺氧复氧诱导的心肌细胞凋亡的影响。方法心肌细胞H9C2分为对照组(Con组)、缺氧复氧组(H/R组)、p38MAPK信号通路抑制剂SB203580组(SB203580组),Con组细胞正常培养,H/R组、SB203580组进行缺氧复氧处理,SB203580组细胞在缺氧前用p38MAPK信号通路抑制剂SB203580预处理24 h。噻唑蓝(MTT)检测细胞存活情况,流式细胞术检测细胞凋亡,二硝基苯肼显色法检测上清中乳酸脱氢酶(LDH)含量,用硫代巴比妥酸比色法检测细胞中丙二醛(MDA)含量,用黄嘌呤氧化法检测细胞中超氧化物歧化酶(SOD)含量,二氯二氢荧光素-乙酰乙酸酯(DCFH-DA)法检测细胞中活性氧(ROS)含量,Western blot检测细胞中p38MAPK、磷酸化p38MAPK(p-p38MAPK)、活化的含半胱氨酸的天冬氨酸蛋白水解酶3(Cleaved Caspase-3)蛋白表达。结果 H/R组、SB203580组细胞存活率低于Con组,凋亡率高于Con组,细胞中MDA、ROS含量高于Con组,培养液上清中LDH高于Con组,细胞中SOD含量低于Con组,细胞中p-p38MAPK、Cleaved Caspase-3蛋白水平高于Con组。SB203580组细胞存活率高于H/R组,凋亡率低于H/R组,细胞中MDA、ROS含量低于H/R组,培养液上清中LDH低于H/R组,细胞中SOD含量高于H/R组,细胞中p-p38MAPK、Cleaved Caspase-3蛋白水平低于H/R组。结论 p38MAPK信号通路抑制剂能够减轻缺氧复氧环境下心肌细胞凋亡和氧化损伤。  相似文献   

7.
目的:探讨p38丝裂原活化蛋白激酶(p38MAPK)在大鼠心肌缺血再灌注损伤中的作用.方法:健康成年雄性SD大鼠随机分为对照组、单纯缺血组、缺血再灌注组、抑制剂组,每组6只.抑制剂组于术前30 min腹腔注射p38MAPK抑制剂SB 203580(5 mg/kg体重).采用夹闭冠状动脉30 min后再灌注2 h的方法建立大鼠心肌缺血再灌注损伤动物模型.采用逆转录多聚合酶链反应(RT-PCR)检测p38MAPK信使核糖核酸(mRNA)表达,免疫组化法检测p-p38MAPK蛋白表达水平及心肌细胞凋亡率.结果:单纯缺血组与对照组比较,大鼠心肌组织中p-p38MAPK的蛋白含量增加,差异有统计学意义(P<0.01),p38MAPK mRNA的表达及细胞凋亡率也增加,但差异无统计学意义(P>0.05).缺血再灌注组与对照组比较,心肌组织中p38MAPK mRNA及p-p38MAPK蛋白水平和心肌细胞凋亡均显著增加,差异均有统计学意义(P<0.05~0.01).与缺血再灌注组比较,抑制剂组大鼠心肌组织p38MAPK mRNA及p-p38MAPK蛋白水平及心肌细胞凋亡均降低,(P<0.05~0.001),差异均有统计学意义.结论:p38MAPK的激活主要发生于再灌注过程;p38MAPK的活化可使缺血再灌注心肌细胞凋亡增加;抑制p38MAPK的活化可以减少缺血再灌注心肌细胞凋亡,减轻缺血再灌注所致的大鼠心肌损伤.  相似文献   

8.
目的 观察氨基胍和泰能对ANP大鼠肠道细菌易位的影响,探讨其防治胰腺感染的效果.方法 50只SD大鼠随机数字法分为对照组、ANP组、氨基胍组、泰能组和氨基胍+泰能组(联合组),各10只.采用胰腺实质均匀注射5%牛黄胆酸钠的方法制作ANP模型,氨基胍组于制模后30min腹腔注射氨基胍100 mg/kg体重;泰能组于制模后6 h腹腔注射泰能60 mg/kg体重;联合组注射2种药.制模后48 h处死大鼠,检测血清淀粉酶和D-乳酸、胰腺组织MPO水平,观察胰腺病理变化,采集胰腺、肝脏、血液、肠系膜淋巴结、腹水行细菌培养.结果 (1)氨基胍组和联合组血清淀粉酶分别为(1173.30±199.73)U/L、(1075.00±200.40)U/L,血清D-乳酸分别为(7.17±1.25)μg/ml、(6.98±1.06)μg/ml,胰腺MPO分别为(0.80±0.07)U/g湿片、(0.78±0.08)U/g湿片,细菌培养平均阳性率分别为20%、16%.较ANP组血清淀粉酶(2234.60±692.06)U/L、血清D-乳酸(12.41±1.78)μg/ml、胰腺MPO(1.59±0.20)U/g湿片、细菌培养平均阳性率60%均有显著改善(P<0.05);(2)泰能组胰腺MPO为(0.80±0.06)U/g湿片、细菌培养平均阳性率为18%,也较ANP组显著改善(P<0.05).但泰能组的血清淀粉酶和D-乳酸与ANP组比较无统计学差异;(3)ANP组胰腺实质有片状坏死、间质充血、大量白细胞浸润,而氨基胍组、泰能组、联合组胰腺组织无明显白细胞浸润.结论 氨基胍和泰能能减少ANP大鼠肠道细菌易位,减少SAP胰腺继发感染.  相似文献   

9.
AIM: To determine functional consequences of this activation, whereby we focused on a potential regulation of the hepatocyte cytoskeleton during ischemia and reperfusion. METHODS: For in vivo experiments, animals received ANP (5 μg/kg) intravenously. In a different experimental setting, isolated rat livers were perfused with KH-buffer ±ANP (200 nmol/L)±SB203580 (2 μmol/L). Livers were then kept under ischemic conditions for 24 h, and either transplanted or reperfused. Actin, Hsp27, and phosphorylated Hap27 were determined by Western blotting, p38 MAPK activity by in vitro phosphorylation assay. F-actin distribution was determined by confocal microscopy. RESULTS: We first confirmed that ANP preconditioning leads to an activation of p38 MAPK and observed alterations of the cytoskeleton in hepatocytes of ANP-preconditioned organs. ANP induced an increase of hepatic F-actin after ischemia, which could be prevented by the p38 MAPK inhibitor SB203580 but had no effect on bile flow. After ischemia untreated livers showed a translocation of Hsp27 towards the cytoskeleton and an increase in total Hsp27, whereas ANP preconditioning prohibited translocation but caused an augmentation of Hsp27 phosphorylation. This effect is also mediated via p38 MAPK, since it was abrogated by the p38 MAPK inhibitor SB203580. CONCLUSION: This study reveals that ANP-mediated p38 MAPK activation leads to changes in hepatocyte cytoskeleton involving an elevation of phosphorylated Hsp27 and thereby for the first time shows functional consequences of ANP-induced hepatic p38 MAPK activation.  相似文献   

10.
目的 探讨趋化因子MCP-1对实验性急性坏死性胰腺炎(ANP)及其并发症的影响.方法 60只SD大鼠按数字表法分为假手术组、ANP组和MCP-1多抗干预组(干预组),各20只.采用3.5%牛黄胆酸钠制备ANP模型,干预组于制模后0、6 h皮下注射抗MCP-1多抗.观察血清淀粉酶、MCP-1、D-乳酸含量变化;观察胰腺、肺、小肠组织病理改变及MCP-1 mRNA的表达;检测胰腺MCP-1蛋白表达;检测肺、小肠髓过氧化酶(MPO)含量.结果 干预组12 h的血淀粉酶、MCP-1、D-乳酸含量分别为(4666±412)U/L、(39.53±8.25)pg/ml和(6.3±2.2)mg/L,均显著低于ANP组的(9611±363)U/L、(63.42±9.32)pg/ml和(9.3±2.1)mg/L(P值均<0.05);胰腺、肺、小肠组织MCP-1 mRNA表达量分别为0.431±0.009、0.211±0.018和0.442±0.017,均显著低于ANP组的0.624±0.010、0.523±0.019和0.569±0.024(P值均<0.05);胰腺MCP-1蛋白表达评分为2.0±0.1,显著低于ANP组的4.0±0.2(P<0.05);肺、小肠组织MPO含量分别为(11.1±3.0)U/g组织和(19.2±2.0)U/g组织,均与ANP组的(39.2±3.1)U/g组织和(13.1±2.1)U/g组织有显著差异(P值均<0.05).结论 早期阻断MCP-1不但可以减轻急性胰腺炎病理损伤,而且能减轻急性肺损伤和肠屏障的损伤程度.  相似文献   

11.
Relying on a certain degree of abstraction, we can propose that no particular distinction exists between animate or living matter and inanimate matter. While focusing attention on some specifics, the dividing line between the two can be drawn. The most apparent distinction is in the level of structural and functional organization with the dissimilar streams of ‘energy flow’ between the observed entity and the surrounding environment. In essence, living matter is created from inanimate matter which is organized to contain internal intense energy processes and maintain lower intensity energy exchange processes with the environment. Taking internal and external energy processes into account, we contend in this paper that living matter can be referred to as matter of dissipative structure, with this structure assumed to be a common quality of all living creatures and living matter in general. Interruption of internal energy conversion processes and terminating the controlled energy exchange with the environment leads to degeneration of dissipative structure and reduction of the same to inanimate matter, (gas, liquid and/or solid inanimate substances), and ultimately what can be called ‘death.’ This concept of what we call dissipative nature can be extended from living organisms to social groups of animals, to mankind. An analogy based on the organization of matter provides a basis for a functional model of living entities. The models relies on the parallels among the three central structures of any cell (nucleus, cytoplasm and outer membrane) and the human body (central organs, body fluids along with the connective tissues, and external skin integument). This three-part structural organization may be observed almost universally in nature. It can be observed from the atomic structure to the planetary and intergalactic organizations. This similarity is corroborated by the membrane theory applied to living organisms. According to the energy nature of living matter and the proposed functional model, the decreased integrity of a human body's external envelope membrane is a first cause of the structural degradation and aging of the entire organism. The aging process than progresses externally to internally, as in single cell organisms, suggesting that much of the efforts towards the restoration and maintenance of the mechanisms responsible for structural development should be focused accordingly, on the membrane, i.e., the skin. Numerous reports indicate that all parts of the human body, like: bones, blood with blood vessels, muscles, skin, and so on, have some ability for restoration. Therefore, actual revival of not only aging tissue of the human body's membrane, but the entire human body enclosed within, with all internal organs, might be expected. We assess several aging theories within the context of our model and provide suggestions on how to activate the body's own anti-aging mechanisms and increase longevity. This paper presents some analogies and some distinctions that exist between the living dissipative structure matter and inanimate matter, discusses the aging process and proposes certain aging reversal solutions.  相似文献   

12.
Abstract: The effect of swimming at night on rat pineal melatonin synthesis was compared with that of light exposure at night. Rats were forced to swim at 0030 hr (lights out at 2000 hr) and sacrificed by decapitation 15 and 30 min later, immediately after swimming. Other groups of animals were exposed to white light (650μW/cm2) for 15 and 30 min at same time. Swimming caused a rapid and highly significant drop in the melatonin content in the pineal gland; however, the activity of N-acetyltransferase (NAT), the supposed rate limiting enzyme in the melatonin production, was not changed. Despite the drop in pineal melatonin levels, serum concentrations of the indole remained elevated in the rats that swam. In contrast, melatonin levels in the pineal and serum of light exposed rats fell precipitously, accompanied by a significant suppression of NAT activity. Since we anticipated that the strenuous exercise associated with swimming may induce release of artrial natriuretic peptide (ANP) from the heart, which in turn could cause the release of pineal melatonin, in a second study we injected physiological saline intravenously to stretch the cardiac muscle and release ANP. Three milliliters of normal saline was injected during the day into the jugular vein of anesthetized rats that were pretreated with isoproterenol to stimulate pineal melatonin production. Animals were killed 15 min after the saline injection, and pineal NAT activity and pineal melatonin levels were measured. The saline injections caused no alteration in the elevated levels of either NAT or melatonin. These data suggest that the disparity in pineal NAT activity (which was high) and pineal melatonin (which was low), in animals swum at night, may not be caused by ANP which is released during strenuous exercise such as swimming.  相似文献   

13.
Abstract: Well-established circadian physiology supports the view that photoperiodic time measurement utilizes the coincidence between the presence of light and a photosensitive phase of a 'biological clock' to alter reproductive status—the so-called external coincidence model of seasonal breeding. In this review, we examine the mechanism whereby photoperiod interacts with presumed suprachiasmatic nuclei activity to allow endogenous melatonin to normally synchronize reproductive activity to the optimal time of year. The Romney Marsh sheep is particularly explored as an experimental model. It is suggested that the on/off activity of seasonal reproduction may be a robust mechanism able to be predictably manipulated by the judicious use of the light/dark cycle and exogenous melatonin, but firmly based on circadian principles.  相似文献   

14.
The immunoneuroendocrine role of melatonin   总被引:19,自引:0,他引:19  
Abstract: A tight, physiological link between the pineal gland and the immune system is emerging from a series of experimental studies. This link might reflect the evolutionary connection between self-recognition and reproduction. Pinealectomy or other experimental methods which inhibit melatonin synthesis and secretion induce a state of immunodepression which is counteracted by melatonin. In general, melatonin seems to have an immunoenhancing effect that is particularly apparent in immunodepressive states. The negative effect of acute stress or immunosuppressive pharmacological treatments on various immune parameters are counteracted by melatonin. It seems important to note that one of the main targets of melatonin is the thymus, i.e., the central organ of the immune system. The clinical use of melatonin as an immunotherapeutic agent seems promising in primary and secondary immunodeficiencies as well as in cancer immunotherapy. The immunoenhancing action of melatonin seems to be mediated by T-helper cell-derived opioid peptides as well as by lymphokines and, perhaps, by pituitary hormones. Melatonin-induced-immuno-opioids (MHO) and lymphokines imply the presence of specific binding sites or melatonin receptors on cells of the immune system. On the other hand, lymphokines such as -γ-interferon and interleukin-2 as well as thymic hormones can modulate the synthesis of melatonin in the pineal gland. The pineal gland might thus be viewed as the crux of a sophisticated immunoneuroendocrine network which functions as an unconscious, diffuse sensory organ.  相似文献   

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Abstract: Herein we documented the response of pineal melatonin production to electrolytes known to be effective on pineal function in view of a possible circadian stage dependence. We studied the release of melatonin by perifused rat pineal glands at 2 different circadian stages corresponding to the middle of the light and dark periods, i.e., respectively, 7 and 19 HALO (Hours After Light Onset, L:D = 12:12). The initial efflux rates were, as expected, much higher in the perifusates of glands removed from rats sacrificed during the dark phase than of those removed during the light phase. After 3 hr of perifusion, melatonin release reached similar levels which were found constant up to the 8th hr of perifusion, whatever the circadian stage. Perifusion of the glands with physiological concentrations for the rat of calcium (5.2 mmol/1) and magnesium (1.34 mmol/1) resulted in a stimulatory effect on the pineal glands removed from rats sacrificed in the middle of the dark period (19 HALO), whereas no effects were observed on the pineal glands removed from rats sacrificed during the light (7 HALO). Lithium (0.28 and 0.55 mmol/1) was ineffective on melatonin release in pineal glands removed 7 and 19 HALO. Our results show differences in the initial efflux rates of melatonin and in the response of perifused pineal glands to calcium and magnesium according to the circadian stage.  相似文献   

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Objectives Peripartal transmission of human immunodeficiency virus (HIV) and Treponema pallidum, the causative agent of syphilis, leads to severe consequences for newborns. Preventive measures require awareness of the maternal infection. Although HIV and syphilis testing in Madagascar could be theoretically carried out within the framework of the national pregnancy follow‐up scheme, the required test kits are rarely available at peripheral health centres. In this study, we screened blood samples of pregnant Madagascan women for HIV and syphilis seroprevalence to estimate the demand for systemic screening in pregnancy. Methods Retrospective anonymous serological analysis for HIV and syphilis was performed in plasma samples from 1232 pregnant women that were taken between May and July 2010 in Ambositra, Ifanadiana, Manakara, Mananjary, Moramanga and Tsiroanomandidy (Madagascar) during pregnancy follow‐up. Screening was based on Treponema pallidum haemagglutination tests for syphilis and rapid tests for HIV, with confirmation of positive screening results on line assays. Results Out of 1232 pregnant women, none were seropositive for HIV and 37 (3%) were seropositive for Treponema pallidum. Conclusions Our findings are in line with previous studies that describe considerable syphilis prevalence in the rural Madagascan population. The results suggest a need for screening to prevent peripartal Treponema pallidum transmission, while HIV is still rare. If they are known, Treponema pallidum infections can be easily, safely and inexpensively treated even in pregnancy to reduce the risk of transmission.  相似文献   

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Duodenal diverticula are a relatively common condition. They are asymptomatic, unless they become complicated, with perforation being the rarest but most severe complication. Surgical treatment is the most frequently performed approach. We report the case of a patient with a perforated duodenal diverticulum, which was diagnosed early and treated conservatively with antibiotics and percutaneous drainage of secondary retroperitoneal abscesses. We suggest this method could be an acceptable option for the management of similar cases, provided that the patient is in good general condition and without septic signs.  相似文献   

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