创伤后应激障碍模型大鼠杏仁核COX及Caspase 3 mRNA表达的变化

目的观察创伤后应激障碍(PTSD)大鼠杏仁核神经元细胞色素氧化酶(COX)及Caspase 3 mRNA的表达变化,进一步认识PTSD行为异常的神经生物学机制。方法采用国际认定的连续单一刺激(single prolonged stress,SPS)方法建立大鼠PTSD模型,取成年健康雄性Wister大鼠40只,随机均分为PTSD模型的1d、4d、7d组及正常对照组。应用酶组化检测COX的表达,采用逆转录-聚合酶链式反应(RT-PCR)技术检测细胞色素氧化酶II亚基(COII)及Caspase 3 mRNA在PTSD杏仁核神经元的表达。结果PTSD大鼠杏仁核神经元细胞质内COX活性和COII mRNA表达水平明显低于正常对照组,SPS7d时最低。Caspase 3 mRNA表达于SPS刺激后逐渐上调,于SPS7d时表达最高。结论创伤后应激障碍模型大鼠杏仁核COX,COII及Caspase 3可能与PTSD的发病机制有关。     

菩人丹超微粉对糖尿病大鼠视网膜神经细胞凋亡及相关基因表达的影响

目的: 探讨菩人丹超微粉(PRD)对糖尿病大鼠视网膜神经细胞凋亡及相关基因表达的影响。方法: 36只Wistar大鼠随机分为3组,正常对照组、糖尿病模型组和PRD治疗组,每组12只。糖尿病模型组和PRD治疗组大鼠均采用链脲佐菌素连续腹腔注射建立2型糖尿病大鼠模型。模型成功建立后,PRD治疗组大鼠给予PRD灌胃3个月。采用脱氧核糖核苷酸末端转移酶介导的缺口末端标记法(TUNEL)检测大鼠视网膜神经细胞的凋亡;SP免疫组织化学染色法检测视网膜B细胞白血病/淋巴瘤相关抗原2(Bcl-2)、B细胞白血病/淋巴瘤相关抗原相关X蛋白(bax)和半胱氨酸天冬氨酸蛋白酶3(caspase-3)蛋白的表达;逆转录聚合酶链反应(RT-PCR)检测bcl-2、bax和caspase-3 mRNA的表达。结果: 糖尿病模型组与正常对照组比较,大鼠视网膜神经细胞凋亡指数、Bax、 caspase-3蛋白及mRNA的表达均明显升高(P＜0.01),Bcl-2蛋白及mRNA的表达、Bcl-2/Bax比值显著降低(P＜0.01);PRD治疗组与模型组比较,大鼠视网膜神经细胞凋亡指数、bax、caspase-3蛋白及mRNA的表达均明显降低,Bcl-2 蛋白及mRNA的表达、Bcl-2/Bax比值显著升高(P＜0.01)。结论: PRD可通过上调Bcl-2的表达及下调Bax及caspase-3的表达,抑制糖尿病大鼠视网膜神经细胞的凋亡,发挥对糖尿病视网膜的保护作用。     

慢性强迫游泳应激抑郁模型大鼠行为学及海马Ca~(2+)/钙调蛋白依赖性激酶Ⅱ的变化

目的 探讨慢性强迫游泳应激(CFSS)模型大鼠行为学的改变和海马神经元Ca~(2+)/钙调蛋白依赖性激酶Ⅱ(CaMKⅡ)的表达变化. 方法 成年健康雄性Wistar大鼠60只,随机分为对照组(30只)和慢性强迫游泳应激组(30只).慢性强迫游泳组强迫游泳4周,制备慢性强迫游泳应激模型;糖水偏好实验、开场实验和Morris水迷宫检测大鼠行为学改变;荧光探针标记法测定海马神经元内Ca~(2+)浓度;胶体金免疫电镜、免疫印迹和RT-PCR检测CaMKⅡ的表达变化. 结果 慢性强迫游泳应激组糖水消耗量和糖水偏好百分比分别为4.114±0.644和86.610±4.450,对照组为8.157±1.105和94.930±2.893,差异有统计学意义(P<0.01);开场实验中慢性强迫游泳应激组和对照组的直立次数分别为1.75±0.96和6.00±0.82,差异有统计学意义(P<0.05);水迷宫实验逃避潜伏期分别为(20.762±3.236)s和(5.632±1.065)s,差异有统计学意义(P<0.01);海马神经元内游离Ca~(2+)浓度分别为(498.94±40.45)nmol/L和(288.91±32.42)nmol/L,差异有统计学意义(P<0.01);CaMKⅡ蛋白和mRNA相对表达水平均高于对照组(P<0.01). 结论 海马Ca~(2+)及CaMKⅡ的表达上调,可能是抑郁模型大鼠情感行为异常的病理生理基础之一.     

PKCζ和PKMζ在创伤后应激障碍大鼠杏仁核的表达

目的探讨创伤后应激障碍(PTSD)大鼠杏仁核PKMζ的表达变化。方法采用单程长时应激(SPS)制备PTSD大鼠模型,将PTSD大鼠分为3组:SPS3d、SPS7d和SPS14d组,正常饲养大鼠作为对照组。取材各组大鼠杏仁核,利用Western blot和免疫荧光染色检测PKMζ蛋白在大鼠杏仁核表达。结果免疫荧光染色结果显示,SPS7d、SPS14d组大鼠杏仁核PKCζ阳性细胞百分数明显多于正常对照组。Western blot结果显示,SPS7d、SPS14d组大鼠杏仁核PKCζ和PKMζ蛋白相对表达水平显著高于正常对照组。结论 PKCζ和PKMζ在PTSD大鼠杏仁核过表达提示其可能参与PTSD的发病过程。     

银杏内酯对拟老年痴呆模型大鼠学习记忆能力的影响

目的:探讨银杏内酯对拟老年痴呆大鼠学习记忆能力影响的可能机制。方法:大鼠海马微量注射冈田酸(OA),银杏内酯灌胃。水迷宫实验检测大鼠学习记忆能力;银染观察大鼠脑内神经原纤维缠结(NFT);免疫组化观察大鼠脑内bax、bcl-2的表达。结果:与对照组比较,模型组大鼠学习记忆能力下降,NFT表达增多明显,bcl-2免疫阳性神经元减少明显,bax免疫阳性神经元增多明显;与模型组相比,银杏内酯组大鼠学习记忆能力明显提高,NFT表达减少明显,bcl-2免疫阳性神经元增多明显,bax免疫阳性神经元减少明显。结论:银杏内酯提高拟老年痴呆大鼠的学习记忆能力可能与其抑制OA对tau蛋白的磷酸化,减少神经细胞的凋亡,从而对神经元产生保护作用有关。     

骨骼肌细胞线粒体通透性转换孔及bcl-2和bax mRNA表达与运动

背景：运动影响骨骼肌细胞的凋亡,而线粒体途径是介导细胞凋亡的一个重要途径。 目的：研究运动对大鼠骨骼肌线粒体通透性转换孔、凋亡调控基因bcl-2和bax表达的影响。 方法：将24只成年雄性SD大鼠随机分为3组：对照组正常饲养,6周游泳训练组进行6周的游泳训练,每周6次,一次性游泳力竭组于第6周进行一次力竭性游泳运动。应用紫外分光光度仪检测各组大鼠骨骼肌线粒体通透性转换孔的开放情况,应用RT-PCR测定大鼠骨骼肌bcl-2和bax mRNA的表达。 结果与结论：与对照组比较,6周游泳训练组大鼠骨骼肌线粒体通透性转换孔的开放程度变化不明显,bcl-2 mRNA的表达显著增加,bax mRNA的表达显著减少,bcl-2/bax mRNA比值显著增大(P < 0.01)。与对照组比较,一次性游泳力竭组大鼠骨骼肌线粒体通透性转换孔开放程度明显增加(P< 0.01),bcl-2 mRNA的表达显著减少,bax mRNA的表达显著增加,bcl-2/bax mRNA比值显著减小(P< 0.01)。说明运动训练可通过改变线粒体通透性转换孔的开放、调节bcl-2/bax表达,调控骨骼肌细胞凋亡。     

杏仁核脑区硫化氢对创伤后应激障碍模型大鼠抑郁样行为的影响

目的:探讨创伤后应激障碍(posttraumatic stress disorder,PTSD)大鼠抑郁样行为改变及杏仁核内胱硫醚β-合成酶(cystathionineβ-synthase,CBS)/硫化氢(hydrogen sulfide,H_2S)水平的变化,并研究补充H_2S对大鼠抑郁样行为的作用及机制。方法:应用连续单一应激方案制备PTSD动物模型,用强迫游泳实验和糖水偏好实验检测大鼠抑郁样行为,用Western blot技术和亚甲基蓝法检测杏仁核CBS/H_2S体系含量,用整体细胞外电生理方法记录杏仁核神经元放电情况。结果:与正常对照组比较,PTSD组大鼠强迫游泳不动时间显著延长(P0.01),糖水偏好率显著降低(P0.01);杏仁核脑区的CBS/H_2S体系含量显著降低(P0.01)。与PTSD组比较,PTSD+硫氢化钠组大鼠强迫游泳不动时间显著减少(P0.01),糖水偏好率显著升高(P0.01)。微量压力注射L-半胱氨酸使杏仁核神经元自发放电频率显著升高(P0.01)。结论:PTSD大鼠通过抑制杏仁核CBS/H_2S体系导致抑郁样行为加重。H_2S拮抗PTSD大鼠抑郁样行为的机制可能与其增加杏仁核神经元放电频率和兴奋性有关。     

心肌再灌注对抑郁大鼠心肌细胞凋亡以及bcl-2、bax和caspase-3表达的影响

目的: 探讨心肌缺血再灌注(I/R)对抑郁大鼠心肌细胞凋亡及凋亡基因bcl-2、bax和 caspase-3 的影响。方法: Wistar大鼠32只,随机分为4组,每组各8只。A组:非抑郁大鼠假手术组;B组:抑郁大鼠假手术组;C组:非抑郁大鼠心肌I/R组;D组:抑郁大鼠心肌I/R组。采用慢性轻度不可预知性应激结合孤养制备抑郁模型,用敞箱实验和液体消耗实验观察大鼠行为改变;运用结扎左冠状动脉前降支的方法复制心肌I/R模型。运用 TUNEL法检测心肌凋亡细胞;运用免疫组化法和逆转录-聚合酶链反应(RT-PCR)方法检测bcl-2、bax和 caspase-3 的表达。结果: (1)与A、B组比较,C、D组心肌细胞凋亡数量显著增加(P<0.01),A、B两组间比较无显著差异;与C组比较,D组心肌细胞凋亡数量显著增加(P<0.05)。(2)与A、B组比较,C、D组Bcl-2、Bax和caspase-3蛋白和mRNA表达显著增加(P<0.01),A、B两组间比较无显著差异; 与C组比较,D组Bcl-2蛋白和mRNA表达显著减少(P<0.05),而Bax和caspase-3蛋白和mRNA表达显著增加(P<0.05)。结论: 心肌缺血再灌注可加重抑郁大鼠缺血心肌细胞凋亡,其机制可能与上调bax和 caspase-3 基因表达、下调 bcl-2 基因表达有关。     

4-苯基丁酸对创伤后应激障碍大鼠认知能力的影响

目的:观察4-苯基丁酸(4-PBA)对创伤后应激障碍(PTSD)大鼠海马神经元内质网应激(ERS)与凋亡的影响,探讨4-PBA改善PTSD大鼠认知能力的机制。方法:36只成年SD大鼠随机分为正常组、PTSD组和4-PBA+PTSD组,每组12只。PTSD组采用单次延长应激(SPS)构建PTSD大鼠模型,4-PBA+PTSD组从造模次日开始每天于固定时间腹腔注射4-PBA(40 mg/kg),连续给药7 d。Morris水迷宫实验检测各组大鼠的学习记忆能力; Western Blot实验检测各组大鼠海马葡萄糖调节蛋白78(GRP78)、CCAAT增强子结合蛋白同源蛋白(CHOP)及B淋巴细胞瘤-2(Bcl-2)、蛋白激酶R样内质网激酶(PERK)-真核翻译起始因子2α(e IF2α)-活化转录因子4(ATF4)信号通路相关蛋白表达的变化。结果:在Morris水迷宫实验中,与对照组比较,PTSD组大鼠学习记忆能力明显减退(P 0.01);与PTSD组比较,4-PBA+PTSD组大鼠学习记忆功能明显改善(P 0.01)。Western Blot实验结果显示,与对照组比较,PTSD组大鼠GRP78、CHOP的表达明显增加(P 0.01),Bcl-2的表达显著减少(P 0.01),PERK、e IF2α、p-eIF2α表达显著增加(P 0.05),与PTSD组比较,4-PBA+PTSD组大鼠GRP78、CHOP的表达明显减少(P 0.01),Bcl-2的表达显著增加(P 0.05),PERK、e IF2α、p-eIF2α表达显著减少(P 0.05)。结论:4-PBA能够通过激活PERK-eIF2α-ATF4信号通路抑制PTSD大鼠海马神经元的ERS和凋亡,进而改善PTSD大鼠的认知能力。     

miR-132基因沉默改善PTSD大鼠焦虑样行为与上调FXR1表达相关

目的研究创伤后应激障碍(PTSD)大鼠前额叶皮质脆性X染色体相关基因1(FXR1)的表达变化,探讨miR-132基因沉默对PTSD大鼠焦虑样行为的影响。方法采用单程长时应激(SPS)制备PTSD大鼠模型,通过侧脑室注射慢病毒建立miR-132基因沉默的PTSD大鼠。将大鼠分为4组:正常组、PTSD组、sh-miRNC组和sh-miR组,通过旷场实验和高架十字迷宫实验检测miR-132基因沉默对PTSD大鼠焦虑样行为的影响。取材各组大鼠前额叶皮质,利用免疫荧光染色、Western blot检测FXR1蛋白表达情况。结果与正常对照组大鼠相比,PTSD组大鼠有显著的焦虑样行为,miR-132基因沉默显著减轻大鼠的焦虑样行为。与正常对照组大鼠相比,PTSD组大鼠前额叶皮质FXR1蛋白表达水平显著降低,而miR-132基因沉默显著上调FXR1蛋白表达水平。结论 miR-132基因沉默显著减轻PTSD大鼠的焦虑样行为与上调FXR1表达水平相关。     

Rates of oxygen consumption and of anaerobic glycolysis in renal cortex and medulla of adult and new-born rats and guinea-pigs

1. Rates of oxygen uptake and of anaerobic glycolysis were estimated in slices from the renal cortex and medulla (a) of adult rats and guinea-pigs, (b) of new-born (1-, 5- and 21-day-old) rats and of guinea-pigs of 1, 12, 21, 24 and 120 hr age.2. In the adult rat, Q(O2) values for the cortex were 12.55 +/- 0.20 (22) and for the medulla: 8.56 +/- 0.17 (22) mul./hr.mg dry weight, while in the new-born rat (24 hr old) they were 10.99 +/- 0.46 (12) and 9.33 +/- 0.18 (9) mul./hr.mg dry weight respectively.3. Values for Q(CO2) (N2) (anaerobic glycolysis) in the 14 hr old new-born rat were in the renal cortex 9.65 +/- 0.35 (5) and in the medulla 7.39 +/- 0.43 (5) mul./hr.mg dry weight; while in the adult they were 2.25 +/- 0.08 (16) and 5.76 +/- 0.14 (16) mul./hr.mg dry weight, respectively.4. In the adult guinea-pig values for Q(CO2) (N2) were of the same order as in the adult rat, though the rate of O(2) uptake was for the cortex 8.12 +/- 0.22 (12) and for the medulla 5.02 +/- 0.23 (11) mul./hr.mg dry weight.5. Though the Q(O2) values in the renal cortex and medulla were smaller in the 1 hr old new-born guinea-pig, they were already increasing in the 12 hr old neonate.6. The results are discussed in the light of enzyme changes occurring during the process of maturation of the nephron as indicated by histochemical observations.     

Modes of reinforcement and gender and culture of experimenter and subject: effects of "alien" and external reinforcement for Japanese and American men and women

In this study, we examined external and "alien" reinforcement (ER and AR. respectively) as a factor in social learning, and studied the combined effects of culture and reinforcement mode. A female (Experiment 1) and a male (Experiment 2) experimenters conducted experimental sessions. Both men and women, who grew up in the same culture as the experimenter, participated and performed the experimental task. A three-way interaction effect of experimenter gender, culture, and reinforcement mode was found on task performance. And the effect was more pronounced for a Japanese experimenter. A female and a male experimenters conducted Experiments 3 and 4, respectively; however participants this time were men and women who grew up in different cultures than the experimenter. Results indicated that the pattern of the subject gender and reinforcement mode interaction effect, when the experimenter was Japanese with American subjects, was exactly opposite to that when the experimenter was American. These experiments showed that AR was as effective for social learning as ER, and that the cultural backgrounds of experimenter and subject influenced AR and ER effectiveness.     

Timing and intensity of early fevers and the development of allergies and asthma

BACKGROUND: Early childhood fevers appear to protect against later allergies and asthma. What is not known is the time in which fevers exert this effect and whether the degree of temperature increase is important. OBJECTIVE: We sought to examine the relationship between the time and degree of early fevers and later allergies and asthma. METHODS: Eight hundred thirty-five children from southeast Michigan were enrolled at birth. Clinic records from their first 2 years were abstracted for episodes of fever. At age 6 to 7 years, children underwent allergy testing. We examined fevers occurring within 6-month intervals in the first 2 years of life and outcomes at age 6 to 7 years. The primary outcome measures were allergic sensitization, asthma, asthma with allergic sensitization, and asthma without allergic sensitization. RESULTS: In the unadjusted analysis each episode of fever between 7 and 12 months of age was associated with a lower odds of allergic sensitization (odds ratio [OR], 0.71; 95% CI, 0.54-0.93) and asthma with allergic sensitization (OR, 0.43; 95% CI, 0.21-0.90) at age 6 to 7 years. Likewise, every 1 degrees C increase in the maximum temperature between 7 and 12 months was associated with a lower odds of allergic sensitization (OR, 0.77; 95% CI, 0.61-0.96) and asthma with allergic sensitization (OR, 0.62; 95% CI, 0.40-0.94). After adjusting for potential confounders, each episode of fever between 7 and 12 months was associated with a lower likelihood of asthma with allergic sensitization (adjusted OR, 0.33; 95% CI, 0.11-0.94) at age 6 to 7 years. CONCLUSIONS: Both the timing and intensity of childhood fevers appear to be important factors in the development of allergies and asthma.     

纳米水平分子成像与诊疗一体化研究进展与挑战

分子成像能以非侵入性的方式重现活体细胞的生理功能和生物学过程,提高疾病的早期和特异性诊断水平。纳米颗粒/材料具有物理性质可控性高、易于表面修饰、血液循环时间长和可功能化等优点,在疾病诊断与治疗中显示出巨大潜力。但如何阐明纳米材料多功能间的内在联系、解决其代谢及安全性等关键机制难题、实现纳米颗粒/材料多功能性到临床多功能...