番茄红素激活JAK/STAT3信号通路减轻离体大鼠心脏缺血再灌注损伤

目的探讨番茄红素对离体大鼠心脏缺血再灌注损伤的心肌保护作用及其可能的机制。方法 SPF级Wistar大鼠65只,随机分为缺血再灌注组(IR组)、药用玉米油组(Vehicle组)、40mg/kg番茄红素组(LP40组)。采用Langendorff灌流装置缺血30min、再灌注60min建立离体大鼠心脏缺血再灌注模型;IR组缺血30min,复灌60min;Vehicle组按每只大鼠2ml药用玉米油予大鼠皮下连续注射5d; LP40组番茄红素按40mg/kg,溶于2ml药用玉米油后皮下注射入大鼠体内,连续注射5d。于术中记录冠脉流量、心率;TTC染色测定心肌梗死面积;TUNEL染色检测心肌细胞凋亡;Western blot检测线粒体相关凋亡蛋白、磷酸化的JAK和STAT蛋白表达;线粒体膜通道孔光度法检测量化MPTP开放程度。结果与IR组相比,LP40组冠脉流量及心率于再灌注后显著恢复;心梗面积百分比、心肌细胞凋亡比例均降低;线粒体相关凋亡蛋白:cytochrome C、APAF-1、cleaved caspase-9、cleaved caspase-3表达水平均下降;心肌线粒体对钙离子诱导MPTP开放的敏感性下降(P0.05),磷酸化的JAK和STAT表达水平增加(P0.05)。结论番茄红素预处理减轻离体大鼠心脏缺血再灌注损伤可能与激活JAK/STAT信号通路相关。     

内源性一氧化氮合酶抑制物上调4周运动大鼠骨骼肌收缩功能和线粒体生物合成

目的:观察内源性一氧化氮合酶(NOS)抑制物非对称性二甲基精氨酸(ADMA)及其信号通路在4周运动大鼠NO水平及骨骼肌收缩功能与线粒体生物合成中的调节作用。方法:建立4周运动大鼠模型,检测离体比目鱼肌对电刺激的单次、强直和疲劳收缩的最大张力;并检测骨骼肌中ATP和线粒体DNA含量以及过氧化物酶增殖体受体γ辅激活因子1α(PGC-1α)、核呼吸因子(NRF)mRNA的表达以反映线粒体生物合成及功能;用高效液相色谱测定血清ADMA浓度;用Western blot法检测骨骼肌中内源性ADMA生成酶PRMT1和ADMA代谢酶DDAH2种亚型以及NOS 3种亚型蛋白的表达;用比色法测定NOS活性及一氧化氮(NO)含量等。结果:与正常对照组相比,运动组大鼠比目鱼肌对电刺激诱导的各种收缩张力均明显增强,比目鱼肌ATP含量、线粒体DNA含量和PGC-1α、NRF mRNA增加显著(P0.01)。运动组大鼠比目鱼肌中构成型NOS(cNOS)的蛋白表达及其NOS活性明显上调(P0.01),而NO含量仅小幅增加(P0.05);同时,4周运动增加大鼠血清ADMA浓度,并伴有骨骼肌DDAH2表达下调。结论:短期耐力运动增强比目鱼肌单次收缩、强直收缩和抗疲劳收缩肌功能,其机制可能与过度增加的cNOS促使ADMA水平反馈性升高,从而维持骨骼肌NO低幅度增加,促进线粒体生物合成有关。     

缺氧及缺氧-复合运动大鼠比目鱼肌肌球蛋白重链组成变化

 目的： 观察缺氧及缺氧复合运动条件下大鼠比目鱼肌肌球蛋白重链(MHC)异构体组成的变化。方法: Wistar大鼠随机分为4组：平原对照组、缺氧组、平原运动组和缺氧复合运动组。缺氧复合运动组大鼠持续暴露于模拟海拔5 000 m高原5周，每天降至4 000 m高原进行游泳运动1 h（6 d/week），运动结束后回升至5 000 m；缺氧组大鼠同时在低压舱内相同海拔高度饲养，但不进行游泳运动；平原运动组和平原对照组在舱外同时饲养，其中平原运动组每天进行游泳运动1 h（6 d/week）。在末次运动结束后24 h处死大鼠，分离后肢比目鱼肌。用含30%甘油的SDS-PAGE电泳分离比目鱼肌MHC异构体，观察MHC异构体组成变化。结果: 平原游泳运动大鼠比目鱼肌重量指数增加，而缺氧复合运动组与平原对照比较无显著差异；大鼠比目鱼肌中段MHC主要由Ⅰ(78％)、Ⅱa(22％)2种异构体组成，缺氧组比目鱼肌MHC由Ⅱa向Ⅰ型转变，单纯运动和缺氧复合运动组与缺氧组变化趋势相同，但缺氧复合运动组显著低于单纯运动组。结论: 慢性缺氧和运动训练后，大鼠比目鱼肌肌纤维MHC组成向能量利用效率更高的慢收缩肌纤维Ⅰ型转变，提示慢性缺氧和缺氧复合运动后比目鱼肌能量利用效率增加。     

缺血预处理对大鼠缺血性脑损伤线粒体钙、细胞色素C水平的影响

目的：观察缺血预处理对大鼠缺血性脑损伤后线粒体钙、细胞色素C水平的影响。 方法： 用大鼠右侧大脑中动脉阻闭制成局灶性脑缺血模型。24只大鼠，每组8只，随机分为缺血预处理组、 模型组和假手术组。缺血预处理组于3 d前给予30 min预缺血及72 h再灌注，实验时行2 h缺血4 h再灌注。用张均田的改良方法测定细胞色素C含量。用火焰原子吸收法检测线粒体钙含量。 结果： 缺血预处理组动物的细胞色素C、线粒体钙与假手术组相比差异显著（P<0.05,P<0.01）, 缺血预处理组与模型组相比差异显著（P<0.05,P<0.01）。 结论： 缺血预处理减少线粒体释放细胞色素C,维持线粒体钙稳态。     

Rho激酶和PKC在环孢素A改善休克血管反应性中的作用及与MPTP的关系

目的：观察Rho激酶和PKC在环孢素A( CsA)改善创伤失血性休克大鼠血管反应性中的作用及与线粒体通透性转换孔(MPTP)开放的关系。方法采用创伤失血性休克大鼠模型和缺氧培养的血管平滑肌细胞(VMSC),观察了Rho激酶和PKC在CsA调节休克血管反应性中的作用,以及对血管平滑肌细胞线粒体MPTP开放的影响,同时观察CsA对休克动物炎症因子TNF-α、IL-1β和IL-6水平的影响。结果 CsA明显改善了休克血管反应性,Rho激酶抑制剂Y27632可显著拮抗CsA恢复休克血管反应性的作用,但是PKC抑制剂staurosporine对CsA的作用无明显影响。 CsA和Rho激酶激动剂U46619都可抑制缺氧后线粒体MPTP的开放程度。休克后大鼠血液中TNF-α和IL-1β的浓度均显著增加,但CsA处理仅使其轻微减少。结论 CsA可以通过抑制线粒体MPTP开放改善休克后血管的低反应性,发挥对创伤休克的治疗作用。 Rho激酶参与了这其中的调节过程。     

自体骨髓单个核细胞移植治疗大鼠后肢缺血

目的　探讨自体骨髓单个核细胞（BM-MNC）移植用于大鼠缺血后肢的治疗后实现血管再生的能力。方法　建立大鼠后肢缺血动物模型,将取于自体的BM-MNC制成细胞悬液注射于缺血部位,分别在移植后2和30d时行动脉造影,用免疫组化方法检测内皮祖细胞（EPC）,毛细血管密度以及测定血管内皮生长因子(VEGF)的表达。结果　缺血肌组织中的EPC含量增高（P<0.01）。BM-MNC移植组在移植早期VEGF表达显著增高（P<0.01）。细胞移植后30dBM-MNC移植组毛细血管密度明显高于其他组（P<0.01）,血管造影可见侧支循环建立。结论　自体骨髓单个核细胞移植于大鼠后肢缺血区能促进血管新生,改善侧支循环,可望成为一种简单有效的治疗下肢缺血的方法。     

后肢急性缺血大鼠模型的构建及评估

背景：目前国内广泛采用大鼠肢体缺血模型对肢体缺血的病理过程和治疗方法进行研究,但在模型的构建及评估上存在一定争议,故急需一种可靠、经济、制作方便的疾病模型。目的：探索不同方式制备的SD大鼠后肢急性缺血模型患肢缺血的程度、持续时间和变化规律,寻找肢体缺血程度适中、稳定,维持时间较长的模型制备方法。方法：随机将72只SD大鼠等分为4组：A组大鼠给予假手术,分离肾动脉水平以下的腹主动脉和髂腰动脉、右股浅动脉、腘动脉、隐动脉;B组大鼠切断右股浅动脉、腘动脉、隐动脉,切除右股浅动脉,建立后肢急性缺血模型;C组大鼠结扎腹主动脉、两侧腹壁阴部动脉,建立后肢急性缺血模型;D组大鼠结扎腹主动脉、髂腰动脉和腰动脉,建立后肢急性缺血模型。结果与结论：造模后2,4,6周,以不同方法建立后肢急性缺血模型的B、C、D组大鼠右后肢肌力弱于A组;4周D组肌力弱于B、C组;6周B、D组肌力仍有弱于C组的趋势。造模后2,4,6周,B、C、D组右后肢静脉血氧分压均低于A组;造模后2,4周,D组低于B、C组;造模后6周D组仍低于C组。造模后2、4周,3个造模组右后肢肌组织部分肌细胞崩解,纤维结缔组织增生,毛细血管增多,炎细胞浸润,且D组病理变化最重。造模后6周,3组纤维结缔组织增生减轻,毛细血管增生、扩张、充血。提示结扎大鼠肾动脉下方腹主动脉、髂腰动脉和腰动脉的后肢缺血模型,缺血程度适中,缺血状态稳定,维持时间较长,制作方便。 中国组织工程研究杂志出版内容重点：肾移植;肝移植;移植;心脏移植;组织移植;皮肤移植;皮瓣移植;血管移植;器官移植;组织工程     

压力和尾吊对大鼠骨骼肌生长的影响

目的建立尾吊和压力大鼠实验模型,比较压力与尾吊对大鼠骨骼肌生长的不同影响。方法 36只雄性SD大鼠随机分为3组:正常对照组、尾吊组和压力组,每组分两个阶段(7、14 d)进行观察。实验结束后测量比目鱼肌与趾长伸肌的湿重体重比、肌纤维横截面积和直径,以及血清中IGF-1浓度。结果压力作用7 d与尾吊7 d后,比目鱼肌湿重体重比、肌纤维横截面积、肌纤维直径都较对照组显著减少(P<0.05);压力组分别减少23.52%、14.26%、13.47%(P<0.05),尾吊组分别减少23.52%、33.07%、25.09%(P<0.05)。压力作用14 d后,各指标分别减少20.51%、-10.49%、-5.73%,都低于7 d压力组的减少量(P<0.05);而尾吊14 d后,比目鱼肌湿重体重比减少了46.15%,显著高于7 d尾吊组的减少量。血清IGF-1浓度和趾长伸肌的改变在压力、尾吊组间没有显著性差异。结论压力对比目鱼肌生长影响的过程不同于尾吊。压力作用初期是以炎症反应为主的组织损伤过程,待肌细胞适应压力环境后,可能产生一定的功能适应性生长。因此,在临床上无论假肢接受腔设计还是康复训练,考虑接受腔压力对内部肌肉损伤的影响,将有助于对残端肌肉组织的保护。     

骨髓间充质干细胞移植治疗肢体缺血的机制

背景：骨髓间充质干细胞移植治疗下肢缺血疾病已取得较好的效果,但其作用机制尚无定论。 目的：探讨骨髓间充质干细胞移植治疗SD大鼠后肢缺血的机制。 方法：结扎肾动脉下腹主动脉、腰动脉和髂腰动脉制备雌性SD大鼠后肢缺血模型。将扩增、纯化的雄性SD大鼠骨髓间充质干细胞注射入大鼠缺血的右后肢股直肌中,对照组右后肢注射等量生理盐水。移植后2,4,6周,制备大鼠右股直肌切片行苏木精-伊红染色、血管内皮生长因子免疫组织化学染色、SRY基因免疫组织化学染色。 结果与结论：移植后2,4,6周移植组右股直肌毛细血管计数、血管内皮生长因子免疫组织化学染色阳性细胞计数均明显高于对照组(P < 0.01)。移植组股直肌切片中SRY免疫组织化学染色阳性细胞出现于毛细血管壁,并散在分布于肌组织中。结果表明局部注射移植骨髓间充质干细胞能促进缺血组织迅速生成大量毛细血管,改善大鼠缺血下肢的血供。骨髓间充质干细胞作为旁分泌细胞,通过增加血管内皮生长因子的分泌,促使大鼠缺血肢体的血管新生。中国组织工程研究杂志出版内容重点：干细胞;骨髓干细胞;造血干细胞;脂肪干细胞;肿瘤干细胞;胚胎干细胞;脐带脐血干细胞;干细胞诱导;干细胞分化;组织工程全文链接：     

慢病毒载体介导HIF-1α基因修饰骨髓间质干细胞促进脑缺血大鼠的神经功能恢复

目的： 探讨静脉注射低氧诱导因子（HIF-1α）修饰的骨髓间质干细胞对脑缺血大鼠神经功能恢复的影响及其可能的作用机制。方法: 利用慢病毒载体介导HIF-1α基因修饰骨髓间质干细胞,获得稳定转染HIF-1α的骨髓间质干细胞,于缺血后3 h经股静脉进行体内移植。在细胞移植后的1、7、14、28 d进行神经功能检查,使用TTC染色观察缺血体积,分别通过TUNEL和pax6、DCX抗体免疫荧光双标分析缺血侧脑组织的神经细胞凋亡及内源性神经干细胞增殖、存活情况。结果: 脑缺血BMSCs-mHIF-1α治疗组在14 d和28 d大鼠神经功能评分显著低于缺血组 (P<0.05),神经功能得到明显改善;脑缺血BMSCs-mHIF-1α治疗组脑梗死灶体积小于缺血组;脑缺血BMSCs-mHIF-1α治疗组缺血侧脑组织的神经细胞凋亡在14 d和28 d明显少于缺血组 (P<0.05);细胞移植后7 d,脑缺血BMSCs-mHIF-1α治疗组在海马区域观察到pax6/DCX细胞数量明显多于缺血组（P<0.05）。结论: 静脉注射HIF-1α修饰骨髓间质干细胞能够促进脑缺血大鼠神经功能恢复;抗凋亡及激活并促进内源性神经干细胞迁移至缺血区可能是静脉注射HIF-1α修饰骨髓间质干细胞治疗脑缺血的机制。     

电针对脑梗塞大鼠脑皮质线粒体通透性转换孔的影响

目的观察电针对脑梗塞大鼠脑组织线粒体通透性转换孔的影响,探讨针刺对缺血神经元保护的线粒体机制。方法将45只成年雄性SD大鼠随机分为对照组、非电针组组(线栓法制造脑梗塞灶)和电针组(梗塞后立即给予电针刺激)。非电针组和电针组分别在梗塞后和针灸后1h、3h、6h取材,提取大脑皮质缺血半暗带线粒体,用流式细胞仪检测各组大鼠脑线粒体内Rhodamine123的荧光强度值(FL1)、线粒体前向角散射(FSC)、线粒体90°侧向角散射(SSC)。结果在1h、3h、6h时,非电针组和电针组与对照组相比FL1、SSC值显著低于对照组值(P<0.05),FSC值均显著高于对照组(P<0.05),具有统计学意义;电针组在上述3个时间点与非电针组相比FL1、SSC值高于非电针组值,但P>0.05,FSC值低于非电针组,但P>0.05,差异均无统计学意义;非电针组内、电针组内FL1、FSC、SSC值各自比较,P>0.05,差异均无统计学意义。结论缺血能显著促使缺血半暗带脑皮质线粒体通透性转换孔的开放,促使线粒体肿胀;未发现针刺在缺血后1h、3h、6h能抑制脑线粒体通透性转换孔的开放。     

Effect of support stimulation on unloaded soleus in rat

We studied the efficacy of plantar support in the prevention of atrophy in a disused soleus muscle during hindlimb suspension (HS). The 14-day investigation involved three groups of hindlimb-suspended male Wistar rats and a group of control rats (C). In all HS groups, the left hindlimbs (L) of the animals were left free. As for the right hindlimbs (R), they were either provided support by an adjustable platform (Sup), or immobilized at the ankle joint in a neutral position (Im), or both supported by the platform and immobilized (Sup+Im). Mass, cross-sectional area (CSA) and slow twitch (ST) fiber percentage (ST%) in the R soleus muscle were similar in the Sup and control groups. In the Sup+Im group, these parameters were significantly lower than in the Sup R and C groups. However, the CSA of ST fibers in the Sup+Im R soleus was significantly higher than in those hindlimbs that were left hanging free. Succinate dehydrogenase activity in ST fibers, and α-glycerophosphate dehydrogenase activity in fast-twitch fibers had decreased in the Sup R as compared with the controls. The maximal rate of ADP-stimulated mitochondrial respiration was increased in the free-hanging Sup L hindlimb in comparison with the control. In conclusion, during HS: (1) hindlimb support prevents slow-to-fast fiber transformation and losses in muscle mass and fiber CSA, but brings about a decrease in metabolic enzyme activity, and (2) hindlimb plantar support attenuates but does not fully prevent ST fiber atrophy in the immobilized soleus. Electronic Publication     

Effect of increased physical activity on growth and differentiation of regenerating rat soleus muscle

Our purpose was to determine the effect of physical exercise on growth and differentiation during regeneration of a slow-twitch muscle. Degeneration/regeneration of the left soleus muscles of Wistar female rats was induced by injection of a snake venom. Muscular differentiation was studied by monitoring the sequential expression of the various myosin heavy chain isoforms (MHCs). Rats were assigned to one of two groups: cage sedentary (n?=?14) or exercised (n?=?16). The exercise programme began 1-day post-injection and the rats ran 1?h/day on a motorized treadmill. Then, 9 and 25 days after venom treatment, the soleus MHC phenotype as determined by immunohistology, electrophoresis and immunoblotting, was studied. At 25 days the expression of MHCs by regenerating soleus was not changed by the increased level of physical activity (P? >?0.05). Exercised and sedentary regenerating muscles contained similar numbers of type-I fibres (100% of total fibres), levels of MHC-1 (85.4 and 89.5% of total MHCs), MHC-2a and M?/?HC-2x/d and their fibres expressed MHC-1 (100% of total fibres) and MHC-2 (45–50%) in the same way. Moreover, the masses of regenerating and nonregenerating soleus were significantly increased by physical exercise (P? 相似文献   

Clenbuterol treatment affects myosin heavy chain isoforms and MyoD content similarly in intact and regenerated soleus muscles

AIMS: Pharmacological treatment with the beta2-adrenoceptor agonist clenbuterol is known to induce a slow-to-fast fibre type and myosin heavy chain (MHC) isoform transition in intact muscle. This study examined the sensitivity of regenerated soleus muscle to 4 weeks of clenbuterol treatment (2 mg kg-1 day-1). METHODS: Female Wistar rats were divided into two groups: vehicle treated (n = 8) and clenbuterol treated (n = 8). The clenbuterol effects on MHC and MyoD expression were examined in soleus muscles either intact, or previously degenerated by venom of the Notechis scutatus scutatus snake. RESULTS: Post-treatment body weights and skeletal muscle weights were not affected by clenbuterol treatment. Muscle protein concentration was higher, and body fat lower in clenbuterol-treated rats than in vehicle-treated animals (P < 0.05). Polyacrylamide gel electrophoresis of soleus myofibrillar protein indicated a clenbuterol-induced decrease in the relative percentage of type I MHC with a concomitant increase in type IIa MHC (31%, P < 0.001). No degeneration effect was observed after 28 days of recovery on the MHC isoform content, and regenerated soleus muscles exhibited the same phenotypical profile as intact soleus muscles, whether or not they were treated with clenbuterol. In intact and in regenerated soleus muscles, MyoD protein levels were significantly increased by clenbuterol treatment (90 and 77%, respectively, P < 0.001). CONCLUSION: These results show that regenerated soleus muscles, comprising a homogeneous population of fibres deriving from satellite cells, have a similar response to clenbuterol as intact muscle arising from at least two discrete populations of myotubes; it is suggested that the activity of signalling pathways involved in the effects of clenbuterol on MHC transitions is not related to the developmental history of myofibres.     

Differential modification of myosin heavy chain expression by tenotomy in regenerating fast and slow muscles of the rat

We have examined the effect of tenotomy on the expression of myosin heavy chains (MyHC) in regenerating fast and slow skeletal muscles. Degeneration/regeneration of the left soleus and plantaris of Wistar male rats was induced by an injection into the muscle belly of a myotoxin (snake venom: Notechis scutatus scutatus). MyHC isoform content of regenerating plantaris and soleus muscles were studied 21 days after muscle injury using an electrophoretic technique. Tenotomy of the regenerating plantaris (mechanical underload) did not alter its MyHC expression (P > 0.05). In contrast, tenotomy of the regenerating soleus increased its relative levels of MyHC-2b (P < 0.05) and MyHC-2x/d (P < 0.01), and decreased its relative level of MyHC-1 (P < 0.01). Tenotomy of the synergistic gastrocnemius (overload) tended to decrease the relative level of MyHC-2b in regenerating plantaris (P < 0.07). The effect of tenotomy of the synergistic gastronecmius on the regenerating soleus was different: a decrease in the relative levels of MyHC-1 (P < 0.05) and an increase in the relative level of MyHC-neonatal (P < 0.01). In conclusion, and in contrast to a regenerating slow muscle, a change of mechanical loading by tenotomy did not seem to markedly alter the expression of mature MyHC phenotype in a fast regenerating muscle.     

Effect of hindlimb unloading on interlimb coordination during treadmill locomotion in the rat

Effects of hindlimb unloading on interlimb coordination were examined in adult rats walking on a treadmill at moderate speed. In the first group of animals, the electromyographic activity (EMG) of soleus muscle of both hindlimbs was recorded after 7 and 14 days of unloading. In the second group, the EMG was recorded daily until the 14th day of unloading. The general organization of locomotion was preserved in the two groups whatever the duration of the unloading. The step cycles of the two hindlimbs were always strictly alternating. However, the locomotor pattern was very irregular. A lateral instability was observed. It was accompanied by an abduction of the hindlimbs, and frequent hyperextensions of the ankle when walking. The EMG analysis showed an increase in step cycle duration and in coactivation duration of the soleus muscles (i.e. in the double stance duration). In the rats recorded daily, mean EMG was dramatically reduced the 1st day of unloading, suggesting a decrease in the neural drive. Taken together, these data indicate that 14 days of hindlimb unloading can alter the neuromuscular pattern during locomotion. It is proposed that these changes are related to changes in the peripheral sensory information.     

Focal mesangial proliferative glomerulonephritis in the rat caused by habu snake venom. A morphologic study.

A new model of focal mesangial proliferative glomerulonephritis in the rat has been produced by intravenous habu snake venom. Glomerulonephritis developed in 70% of rats surviving the first 6 hours after venom administration. The earliest ultrastructural change (10 minutes after venom) was the presence of loose platelet aggregates and free granules in the capillary lumen and mesangium. This was followed by dissolution of the matrix and endothelial damage. Between 4 and 24 hours, a characteristic focal and segmental ballooned lesion of glomerular capillaries developed. In these lesions, from 3 days onwards a segmental mesangial proliferation occurred, which persisted until sacrifice at 21 days.     

β-淀粉样蛋白对原代培养大鼠海马神经细胞钙稳态和线粒体线粒体通透性转运孔道的影响

目的 研究β-淀粉样蛋白(β-amyloid)对原代培养的大鼠脑海马神经细胞内钙稳态和线粒体通透性转运孔(mitochortrial permebility transition pore,MPTP)的影响,探讨其神经毒性作用的机制.方法 原代培养8d后的Wistar大鼠脑海马神经细胞,用老化的Aβ25-35对其进行1,10和20 μmol/L剂量的染毒,培养24和48h后观察海马神经细胞形态、游离钙浓度、Ca2+-ATP酶活性、线粒体膜电位,应用Western blot方法分析MPTP组成蛋白表达情况.结果 随着Aβ25-35剂量的增加和染毒时间的延长,可以观察到原代培养的海马神经细胞呈现出弥漫性肿胀、开始变形、出现空泡、胞体边缘模糊的形态变化;原代培养海马神经细胞内的游离钙离子的浓度也呈逐渐上升趋势,其中Aβ25-35 20 μmol/L组在24h和48 h时,细胞内钙离子浓度分别为(31.04±4.16)和(32.80 ±0.43),均显著高于对照组(20.95±4.04)和(22.23 ±0.49)(P ＜0.05);Ca2+-ATP酶活性随着染毒剂量和染毒时间增加明显降低(P＜0.05),其中Aβ25-3520 μmoL/L组在24h和48h时,细胞内Ca2+-ATP酶活性为(2.14±0.01)和(1.10±0.05) U/mgprol,均显著低于对照组(5.17±0.08)和(4.57±0.06)(P＜0.05);线粒体膜电位Aβ25-35 20μmol/L组在24h和48 h时,细胞内线粒体膜电位分别为(20.34 ±7.05)和(19.05±6.15),均显著低于对照组(38.47 ±0.72)和(40.07±1.26)(P＜0.05);有明显剂量反应关系;MPTP孔道蛋白的WB结果显示蛋白表达量随着染毒剂量增加而增加.结论 Aβ25-35通过破坏细胞的钙稳态激活MPTP孔道影响线粒体功能从而发挥神经毒性作用.     

脑淋巴引流障碍加重大脑中动脉阻塞大鼠缺血性脑水肿

目的：探讨脑淋巴引流阻滞对脑缺血性的影响。方法：将76只Wistar大鼠随机分为大脑中动脉阻塞(MCAO)组和。MCAO加脑淋巴引流阻断组(MCAO CLO)组，在术后24、48、72h分别检测缺血区脑组织水、电解质含量。结果在手术后各时间点，MCAO大鼠缺血区脑组织的含水率、Na^ 含量、Ca^2 含量均显著增加，而K^ 显著下降。MCAO CLO组大鼠的上述指标变化更为显著。结论：脑淋巴引流障碍能明显加重MCAO后缺血性脑水肿。