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1.
目的:探讨硬膜外皮质电刺激(EECS)对急性颅脑脑损伤(ACCI)后的影响.方法:SD大鼠24只,随机分为A组(假损伤组),B组(损伤组)和C组(治疗组),侧方液压打击损伤(LFPI)大鼠脑组织建立ACCI模型后,C组给予硬膜外电刺激治疗.术后24小时处死动物,检测A组脑组织含水量、血清神经元特异性烯醇化酶(NSE)含量与B、C组上述指标的差异.结果:与A组相比,B组与C组脑组织含水量明显增加(P<0.01),与B组相比,C组大鼠脑含水量减少(P<0.05),差异有统计学意义;与A组相比.B组与C组大鼠血清NSE明显增加(P<0.01),与B相比,C组大鼠大鼠血清NSE明显减少(P<0.01),差异有统计学意义.结论:EECS可减轻ACCI后脑水肿,降低血清NSE水平,从而起到脑保护的作用.  相似文献   

2.
复方银杏胶囊镇痛作用及其机制的实验研究   总被引:3,自引:0,他引:3  
目的:研究复方银杏胶囊的镇痛作用及其机制.方法:大鼠电刺激法测定痛阈;用试剂盒比色法测定脑组织中谷氨酸的含量;原子吸收光谱法测定脑组织中钙离子(Ca2 )浓度;免疫组织化学ABC法观察脑组织中N-甲基-D-天门冬氨酸Ⅰ型受体(NMDAR1)的分布.结果:复方银杏胶囊350 mg/kg可显著提高大鼠电刺激嘶叫阈(P<0.05),700 mg/kg显著减少小鼠脑组织中谷氨酸的释放以及脑内钙离子浓度(P<0.05);复方银杏胶囊700 mg/kg、350 mg/kg可明显减少疼痛模型小鼠大脑皮层NMDAR1阳性细胞数(P<0.01,P<0.05).结论:复方银杏胶囊具有良好的镇痛效应,其镇痛作用可能与拮抗NMDA受体从而抑制脑组织中谷氨酸的释放及钙离子内流有关.  相似文献   

3.
电刺激猫小脑问位核和顶核可以影响下丘脑外侧区神经元的电活动,其中有一些神经元是葡萄糖敏感神经元.这一结果揭示小脑不仅具有经典的躯体运动调节功能,同时也可以通过小脑-下丘脑通路参与机体非躯体活动的调节.  相似文献   

4.
在戊巴比妥钠麻醉的猫,电刺激下丘脑外侧区(LHA)和腹内侧核(VMN)可引起小脑皮层第Ⅵ和Ⅶ小叶浦肯野细胞和非浦肯野细胞抑制性、兴奋性和抑制-兴奋性的电活动,但以抑制性活动为主;这些反应的潜伏期多数为10-20ms,但也可长达90ms;一般刺激LHA比刺激VMN更有效。刺激下丘脑所激发的小脑神经元抑制性电活动可为静脉注射组胺H_1受体阻断剂扑尔敏所阻断。本文对上述观察的可能作用作了讨论。  相似文献   

5.
外周信息主要通过神经末梢释放谷氨酸激活促离子型谷氨酸受体( ionotropic glutamate receptor,iGluRs),调节间位核神经元的兴奋性。研究旨在探讨模拟失重对大鼠小脑间位核iGluRs 表达的影响。采用大鼠尾部悬吊法建立模拟失重动物模型,按体重配对原则随机将大鼠分为尾部悬吊14 d组和正常同步对照组。采用免疫组织化学ABC染色法观测大鼠小脑间位核iGluRs ( NMDAR-1、AMPAR-2和KAR-2)免疫阳性神经元数量的变化。结果表明正常对照组大鼠小脑间位核内有iGluRs免疫阳性神经元存在。大鼠吊尾14 d后,大鼠小脑间位核iGluRs免疫阳性细胞数明显增多( P<0.05)。结论模拟失重可使大鼠小脑间位核神经元网络的兴奋性增高。这一变化可能与模拟失重引起的调控肌肉运动的中枢神经系统的适应性变化有关。  相似文献   

6.
在麻醉并麻痹的猫上观察到:刺激中缝背核(DR)可引起小脑皮层浦肯野细胞(PC)兴奋或抑制(主要是抑制);由被动性腕关节屈伸运动刺激引起的外周本体传入可以增强或减速PC对DR刺激的反应。这些结果表明中缝-小脑5-HT能纤维的传入活动可以调制PC的放电活动,并与外周传入有相互作用。  相似文献   

7.
目的:研究HLRP分子在大鼠脑中的细胞定位和表达特点,观察LPS刺激对动物脑HLRP表达的影响。方法:对原代培养的大鼠神经元、星形胶质细胞、小胶质细胞和大鼠脑组织冰冻切片分别进行免疫荧光染色,观察HLRP的细胞定位和表达特点;给大鼠侧脑室注射LPS,提脑组织蛋白,进行Western blot检测,半定量分析LPS刺激后,大鼠脑HLRP的表达变化。结果:①HLRP选择性表达于部分神经元的细胞核中,正常的星形胶质细胞和小胶质细胞不表达HLRP。②从嗅脑到脑干各节段,HLRP在大鼠脑组织中均匀分布,未发现HLRP阳性神经元聚集的现象。③侧脑室注射LPS 1天以后,HLRP表达明显升高(P<0.05)。结论:大鼠脑中正常表达HLRP,侧脑室注射LPS能刺激HLRP表达。  相似文献   

8.
本文研究了刺激外周神经及中缝背核区对猫小脑皮层浦肯野细胞(Purkinje Cell,PC)电活动的影响。在清醒的去大脑猫上记录刺激桡深神经(NRP)及腓深神经(NPP)时PC的电变化,并观察刺激中缝背核区对PC自发放电以及肢体神经传入冲动诱发活动的影响。结果表明,刺激NPP和NRP均可引起小脑皮层第Ⅴ和第ⅦA小叶的PC产生兴奋或抑制反应。刺激中缝背核区对PC自发放电以及诱发活动主要起抑制性影响。  相似文献   

9.
目的:探讨不同声强超声对孕鼠子宫收缩及胎鼠神经损伤的影响及机制。方法:将32只孕鼠随机分为A(0)组、B(2)组、C(4)组、D(8)组,每组各8只,分别接受声强为0 W cm~(-2)、2 W cm~(-2)、4 W cm~(-2)和8 W cm~(-2)的超声辐照20 min。记录孕鼠子宫收缩及子宫平滑肌ATP酶的活力,检测胎鼠大脑皮层与海马神经元凋亡及胆碱能神经系统相关酶的活力。结果:超声增加孕鼠子宫收缩频率、收缩幅度、收缩张力和子宫活动度(P均0.05),降低孕鼠子宫平滑肌中钠钾ATP酶、钙ATP酶和钙镁ATP酶的活性(P均0.05)。超声降低胎鼠大脑皮层和海马中Bcl~(-2)水平(P0.05),增加Bax和Caspase-3水平(P均0.05)。以及促进乙酰胆碱酯酶活力,降低乙酰胆碱和乙酰胆碱转移酶水平(P均0.05)。且4 W cm~(-2)和8 W cm~(-2)的超声比2 W cm~(-2)超声对这些指标的作用更强。结论:4 W cm~(-2)和8 W cm~(-2)超声可能通过降低ATP酶的活性促进孕鼠子宫平滑肌收缩,并可引起胎鼠大脑皮层和海马神经元损伤,机制可能与胆碱能神经元系统失衡有关,2 W cm~(-2)声强的超声对胎鼠神经元损伤甚小。  相似文献   

10.
下橄榄小脑系统是六十年代中期Eccles等揭示小脑皮层神经元环路以来在小脑功能研究中引人注目的一个侧面。近年来,用电镜、放射自显影和辣根过氧化酶等技术对下橄榄核的微细结构、攀缘纤维(CF)的起源和分布做了系统的研究。在电生理学方面发现并重视了攀缘纤维传入的抑制作用,对下橄榄细胞和小脑浦肯野细胞兴奋时复合峰电位形成的机制有较深入的了解,发展了一些专门或主要应用于下橄榄小脑系统研究的新技术和实验方法。  相似文献   

11.
Following treatment, cypermethrin and fenvalerate, were found to have inhibitory effect on serum acetylcholine esterase (AchE) activity of cattle and buffalo experimentally infested with B. microplus. The pattern of AchE activity in infested-pyrethroid-treated group was found to be significantly different from either healthy or tick-infested control. There was transient increase in the enzyme activity initially, followed by gradual decline and subsequent increase leading to normal level within 7 days of pyrethroid treatment. The enzyme activity was found to be low in buffalo than in cattle and the values remained below normal level up to day 7 in tick-infested group. The reversion of AchE activity to normal level in pyrethroid-treated group indicated that these compounds are prompt and safe ixodicides with least residual effect. The present investigation concludes that estimation of serum AchE might help in the clinico-biochemical diagnosis of tick toxin and pyrethroid toxicity in cattle and buffalo treated with these pyrethroids against tick infestation.  相似文献   

12.
During the development of kindling by daily electrical stimulations applied to the left amygdala of rats, concentrations of the polyamines putrescine, spermidine, and spermine were measured in the left amygdala and the remainder of the cerebrum. A significant increase of putrescine concentration appeared first at the left amygdala in prekindled rats and then propagated to the remainder of the cerebrum with the development of kindling. This increase in putrescine concentration in the left amygdala was higher in prekindled rats than in fully kindled rats and lasted for at least 24 h after the final kindling stimulation. The concentrations of spermidine and spermine were slightly increased in a fully kindled state. To clarify the role of putrescine in kindling, the development of amygdaloid kindling was examined in rats after microinjections of alpha-difluoromethylornithine, a specific inhibitor of polyamine synthesis, and putrescine into the ipsilateral amygdala. Pretreatment with alpha-difluoromethylornithine (50 nmol) for 10 days accelerated both the development of behavioral kindling and the propagation of the afterdischarge from the left amygdala to the frontal cortex. In contrast, pretreatment with putrescine (200 nmol) for 10 days retarded the development of kindling. These results suggest that the increase in putrescine concentration in the kindled brain has an inhibitory effect on the development of kindling.  相似文献   

13.
就缺锌对大鼠血液皮质醇和促肾上腺皮质激素(ACTH)含量以及大脑皮质NO合酶活性的影响进行了研究,生长大鼠随机分为3组,即缺锌组,对喂组和缺锌补锌组(先饲喂缺锌饲料21天后再补锌),饲养实验的持续时间为35d。与对喂组比较,缺锌组大鼠血液中皮质醇含量显著升高,而血液ACTH浓度以及大脑皮质NO合酶活性明显降低,此结果提示锌可影响下丘脑-垂体一肾上腺皮质轴和NO合酶的代谢。  相似文献   

14.
A method has been developed to quantitate megakaryocytopoiesis in culture by measuring acetylcholinesterase synthesized in vitro. Murine marrow cells, treated with diisopropylfluorosphosphate (DFP) to inactivate initial acetylcholinesterase (AchE) present in megakaryocytes and contaminating blood, were set up in Iscove's medium supplemented with 15% DFP-treated horse serum +/- pokeweed mitogen-stimulated spleen cell conditioned medium (PWM-SCM) in 96-well microplates. Following the culture period, Triton X-100, dithiobisnitrobenzoic acid (DTNB), and acetylthiocholine iodide were added to each well. AchE synthesized in culture cleaved acetylthiocholine to thiocholine, which stochiometrically reduced the colorless indicator DTNB to a highly colored product. Thirty minutes following the addition of substrate, the plates were assayed for activity with a vertical recording photometer. When platelets, freshly prepared bone marrow cells, or cultured marrow were assayed by this method, a linear relationship was observed between optical density (OD) and the number of cells assayed. Moreover, a linear relationship between the number of AchE-positive megakaryocytes determined histochemically and AchE activity determined spectrophotometrically was observed. Red cells exhibited no activity. Inhibitor studies demonstrated that the activity measured was true AchE. Separation of marrow by density gradient centrifugation showed that the megakaryocyte enriched fraction contained all the AchE while the megakaryocyte depleted fraction contained none. From the data we conclude that this rapid, semiautomated method quantitates megakaryocytic AchE synthesis in culture, and that this method will be a useful assay system for the detection of factors that influence megakaryocytopoiesis.  相似文献   

15.
The activity of acetylcholinesterase (AchE) increases rapidly after the gastrula stage of sea urchin development. In this report, changes in activity and in the molecular differentiation of AchE were investigated. AchE activity increased slightly during gastrulation and rose sharply thereafter, and was dependent on new RNA synthesis. No activity of butyrylcholinesterase was found. Morphogenesis in sea urchin embryos was inhibited by the AchE inhibitor eserine, which specifically inhibited arm rod formation but not body rod formation. Spicule formation and enzyme activity in cultured micromeres were inhibited by eserine in a dose-dependent manner. During gastrulation, two molecular forms of AchE were detected with polyacrylamide gel electrophoresis. The appearance of an additional band on the gel was consistent with the occurrence of a remarkable increase in the enzyme activity. This additional band appeared as a larger molecular form in Anthocidaris crassispina, Hemicentrotus pulcherrimus, Stomopneustes variolaris, and Strongylocentrotus nudus, and as a smaller form in Clypeaster japonicus and Temnopleurus hardwicki. These results suggest that the change in the molecular form of AchE induced a change in enzymatic activity that in turn may play a role in spicule elongation in sea urchin embryos.  相似文献   

16.
Only one form of acetylcholinesterase (AchE) was detected in Hemicentrotus pulcherrimus embryos. In H. pulcherrimus embryos as well as in the other sea urchin embryos, AchE activity begins to increase rapidly after gastrula stage.
Purification of AchE from plutei has been carried out by the procedure including affinity chromatography. Purified AchE had the activity 14,600 times higher than that of homogenate, and the final yield of AchE was 8%. The enzyme seems to be electrophoretically homogeneous, and has a molecular weight of 3 × 105 as determined by Sepharose CL–6B column chromatography.  相似文献   

17.
Acetylcholinesterase (AchE) activity in erythrocytes and blood levels of cortisol and insulin were investigated in athletes training under different bioenergetic conditions (sprinters, middle-distance runners, and marathoners). The groups of sprinters and marathoners had a decreased enzyme activity compared to nonathletes (p < 0.05). In response to a standard exercise, load AchE activity increased in the groups of middle-distance runners and marathoners. A relationship was observed between the level of AchE activity and the cortisol-to-insulin ratio in the blood. This ratio is specific to the type of bioenergetic conditions and increases in the following order: controls, middle-distance runners, sprinters, and marathoners. In vitro experiments revealed an effect of insulin on AchE activity. This effect was significantly lower in sprinters than in the control group. A reduction in AchE activity and an increase in the cortisol-to-insulin ratio are considered as factors increasing metabolic turnover in athletes, mainly, lipid turnover. This mechanism ensures effective mobilization of substrates at the start of physical exercise and their recovery after. The observed relationship between the insulin level and the AchE activity may prove to be a mechanism of regulation of the insulin level. This relationship may change during adaptation to physical exercise, as in the case of sprinters, when the sensitivity of AchE to the inhibitory effect of insulin is decreased. A high blood level of cortisol and insulin is a distinctive feature of sprinters, which provides for a higher turnover of carbohydrates. In marathoners, low AchE activity leads to an increased effect of acetylcholine, which is manifested by an increased cortisol level and a decreased insulin level, thus providing for a higher lipid turnover.  相似文献   

18.
提取水母胶原蛋白,观察其体内外抗氧化作用。体外采用邻苯三酚自氧化法观察水母胶原蛋白对超氧阴离子(·O2-)的清除作用,采用Fenton反应体系观察对羟自由基(·OH)的清除作用;体内观察水母胶原蛋白对小鼠血清、肝脏、大脑中超氧化物歧比酶(SOD)、过氧化氢酶(CAT),丙二醛(MDA)含量的影响。结果表明:水母胶原蛋白对·O2-、·OH具有良好的清除作用,呈一定的剂量依赖关系,能明显提高小鼠血清、肝脏、大脑中的SOD、CAT含量,能在一定程度上降低血清、肝脏、大脑中的MDA水平。因此,水母胶原蛋白具有显著的抗氧化生物活性。  相似文献   

19.
Oögenesis and the physiological activity of the corpora allata were studied in adult females of the Egyptian locust (Anacridium aegyptium), in ovarian diapause, after electrical stimulation in vivo of the pars intercerebralis. This stimulation provokes (1) a decrease in the quantity of fuchsinophilic material present in the median neurosecretory cell bodies and in the internal cardiac tract, (2) an increase in the physiological activity of the corpora allata (measured by its chromatropic effect on larvae of Locusta), and (3) rupture of the ovarian diapause (advance of maturation of the oöcytes and oviposition by 5 months, and initiation of the ovarian cycle).In the control animals, the same electrical stimulations of various regions of the central nervous system (tritocerebrum, first ganglion of the abdominal cord) have no effect on these phenomena.In allatectomized females, electrical stimulations of the pars intercerebralis are followed by a slight growth of oöcytes, without a deposit of yellow vitellus. The diapause is not broken. Section of the allatocardiac nerves or rupture of the allatocardiac and allato-suboesophageal nervous connexions do not change the physiological state of the corpora allata. In the case of females in which the corpora allata have been disconnected, electrical stimulations of the pars intercerebralis succeed in activating the corpora allata and breaking the ovarian diapause. The aggregate of these results confirms that in locusts the control of the brain over the physiological activity of the corpora allata is above all neuroendocrine.  相似文献   

20.
蛇床子素粉剂对玉米象成虫的杀虫活性及酶活性的影响   总被引:2,自引:0,他引:2  
研究1.0%蛇床子素(osthole)粉剂对玉米象Sitophilus zeamais Motschusky成虫的杀虫活性及其对玉米象成虫羧酸酯酶、乙酰胆碱酯酶、谷胱甘肽S-转移酶及蛋白质活性的影响。结果表明,1.0%蛇床子素粉剂对玉米象成虫有很好的杀虫活性,处理玉米象成虫3d后,0.8mg/kg以上剂量的蛇床子素粉剂对玉米象成虫的校正死亡率达100%;用0.19mg/kg蛇床子素粉剂处理玉米象成虫2d后,试虫体内乙酰胆碱酯酶、羧酸酯酶和蛋白质活性均表现出受抑制,而谷胱甘肽S-转移酶活性随处理时间的延长整体趋势表现出被诱导。  相似文献   

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