对药酸枣仁-合欢花对抑郁模型大鼠海马CA3区细胞凋亡及caspase-12表达的影响

目的:研究对药酸枣仁(SZS)-合欢花(AJF)对抑郁模型大鼠海马CA3区细胞凋亡及半胱氨酸天冬氨酸特异性蛋白酶-12(caspase-12)表达的影响,从内质网应激(ERS)角度探讨其抗抑郁作用机制。方法:将雄性SD大鼠按随机数字表法分为正常对照组(Control)、模型组(CUMS)、对药酸枣仁-合欢花组(SZS+AJF)、盐酸文拉法辛组(Venlafaxine),采用孤养加慢性不可预见性温和应激(CUMS)建立抑郁症大鼠模型,并用旷场实验评价各组大鼠行为学改变。应用DNA原位末端缺口标记(TUNEL)法检测海马CA3区神经元凋亡情况,应用免疫组化检测海马CA3区caspase-12表达。结果:与Control组比较,CUMS组大鼠旷场实验得分降低,海马CA3区细胞凋亡率及caspase-12表达显著增加。与CUMS组比较,SZS+AJF组、Venlafaxine组大鼠旷场实验得分显著增加,海马CA3区细胞凋亡率及caspase-12表达显著减少。结论:对药酸枣仁-合欢花能显著改善抑郁模型大鼠的抑郁症状,降低海马CA3区caspase-12表达,抑制海马CA3区细胞凋亡。     

高压氧通过激活CREB/BDNF信号通路减轻阿尔茨海默病小鼠海马神经元突触损伤

目的:探讨高压氧(hyperbaric oxygen,HBO)对阿尔茨海默病APP/PS1转基因(trangenic,TG)小鼠海马神经元突触损伤的影响及其作用机制。方法:将6月龄雄性APP/PS1 TG小鼠随机分为TG组、HBO组及环磷酸腺苷反应元件结合蛋白(cAMP response element binding protein,CREB)抑制剂H89组,每组10只;另取10只同龄雄性野生型(wild-type,WT)C57BL/6小鼠作为阴性对照组(WT组)。HBO和H89组小鼠进行高压氧治疗6个疗程;WT组及TG组小鼠不给予治疗。Morris水迷宫实验检测各组小鼠学习记忆能力;筑巢实验检测小鼠智力改变;尼氏染色检测各组小鼠海马神经元中尼氏体表达;real-time PCR检测小鼠海马区CREB及脑源性神经营养因子(brain-derived neurotrophic factor,BDNF)mRNA的表达;Western blot检测小鼠海马区突触素(synapsin,SYN)、突触后致密区蛋白95(postsynaptic density protein 95,PSD95)、生长相关蛋白43(growth-associated protein 43,GAP43)、CREB、磷酸化CREB(p-CREB)及BDNF的蛋白水平。结果:与WT组相比,TG组小鼠学习记忆能力降低,筑巢分数显著降低,海马区尼氏体数量显著减少,CREB及BDNF mRNA相对表达显著减少,SYN、PSD95、GAP43、p-CREB及BDNF蛋白水平显著降低(P0. 05)。与TG组相比,HBO组小鼠学习与记忆能力改善,小鼠筑巢分数显著增加,海马区神经元排列整齐且尼氏体数量增加,CREB及BDNF mRNA相对表达显著增加,SYN、PSD95、GAP43、p-CREB及BDNF蛋白水平显著升高(P0. 05)。与HBO组相比,H89组小鼠学习记忆能力及筑巢分数显著降低,海马区尼氏体数量减少,CREB及BDNF mRNA相对表达显著减少(P0. 05),SYN、PSD95、GAP43、p-CREB及BDNF蛋白水平显著降低(P0. 05)。结论:HBO能改善APP/PS1 TG小鼠的学习记忆能力,其机制可能与激活CREB/BDNF信号通路,减轻小鼠海马神经元突触损伤有关。     

TRAF6对抑郁症大鼠海马区神经元细胞损伤和免疫紊乱的调节

目的 探讨肿瘤坏死因子受体相关因子6(TRAF6)对慢性不可预知性轻度应激(CUMS)大鼠的抗抑郁作用。方法 将40只健康SPF级SD大鼠随机分为对照组、模型组(CUMS组)、CUMS+sh RNA-NC组和CUMS+TRAF6-sh RNA组,每组10只。除对照组外,所有大鼠每天随机接受CUMS刺激,5周后,分别向CUMS+sh RNA-NC组和CUMS+TRAF6-shRNA组大鼠海马区注射慢病毒包被的sh RNA-NC和TRAF6-shRNA序列。RT-PCR和Western blot检测TRAF6 m RNA和蛋白的表达; ELISA检测大鼠血清中5-羟色胺(5-HT)、5-羟吲哚乙酸(5-HIAA)、TNF-α、i NOS、IL-6和IL-10的含量;酶法测定大鼠血清血脂; HE染色观察海马区病理状况; TUNEL染色检测海马区细胞凋亡情况; Western blot检测海马谷氨酸转运体(GLT-1)和脑源性神经营养因子(BDNF)及凋亡蛋白的表达。结果 与对照组相比,CUMS组大鼠海马区TRAF6 m RNA和蛋白表达量明显上调(P 0. 05),GLT-1和BDNF蛋白表达显著下调(P 0. 05),血清中5-HT和5-HIAA水平显著较低(P 0. 05),TC、TG和LDL-c水平较高(P 0. 05),HDL-c水平较低(P 0. 05);大鼠血脂代谢紊乱,海马区神经元数量减少,核固缩;凋亡细胞数目明显较多(P 0. 05),Bax/Bcl-2及cleaved Caspase3/Caspase3比值显著上调(P 0. 05); TNF-α、i NOS、IL-6和IL-10含量明显较高(P 0. 05)。与CUMS组相比,CUMS+TRAF6-sh RNA组大鼠海马区TRAF6 m RNA和蛋白表达量明显下调(P 0. 05),GLT-1和BDNF蛋白表达显著上调,血清5-HT和5-HIAA水平较高(P 0. 05),TC、TG和LDL-c水平较低(P 0. 05),HDL-c水平较高(P 0. 05);海马区神经元完整,很少有核固缩;凋亡细胞数目明显较少(P 0. 05),Bax/Bcl-2及cleaved Caspase3/Caspase3比值显著下调(P 0. 05),TNF-α、i NOS、IL-6含量显著较低(P 0. 05),IL-10含量较高(P 0. 05)。结论 敲低TRAF6水平治疗抑郁症大鼠可能是通过调节大鼠神经递质、抑制海马神经元凋亡并抑制炎症反应来实现。     

海马齿状回的内质网应激参与AD模型大鼠空间学习记忆损伤的机制

目的:探讨海马齿状回(DG)的内质网应激(ERS)损伤阿尔茨海默病(AD)大鼠空间学习和记忆功能的分子机制。方法:60只SD系雄性大鼠(3月龄)随机分为空白(control)组和AD模型(AD)组,AD大鼠侧脑室注射1次链脲佐菌素(2.4 mg/kg),3 d后开始腹腔注射D-半乳糖(60 mg·kg-1·d-1)共6周,而control大鼠以相同方法注射生理盐水。Morris水迷宫评估大鼠的空间学习记忆能力;透射电镜观察大鼠海马DG区超微结构;Western blot法检测海马DG区的葡萄糖调节蛋白78(GRP78)、蛋白激酶R样内质网激酶(PERK)、Ca2+/钙调蛋白依赖性蛋白激酶II(CaMKII)、细胞外信号调节激酶(ERK)和脑源性神经营养因子(BDNF)的水平,并通过腹腔注射ERS抑制剂4-苯基丁酸(4-PBA)和ERK通路抑制剂PD98059探讨DG区ERS损伤AD大鼠空间学习和记忆功能的下游机制。结果:与control大鼠比较,AD大鼠海马DG区的超微结构明显受损,包括突触结构损伤、粗面内质网排列紊乱及核糖体脱落,其ERS标志蛋白GRP78和p-PERK的水平显著升高(P0.05)。与control大鼠比较,AD大鼠的空间学习和记忆能力显著下降(P0.05),海马DG区p-CaMKII、p-ERK和BDNF的水平显著降低(P0.05);4-PBA可改善AD大鼠的空间学习和记忆能力,同时提高海马DG区p-CaMKII、p-ERK和BDNF的水平(P0.05)。利用PD98059抑制ERK通路可反转4-PBA增加AD大鼠海马DG区BDNF表达的作用(P0.05)。结论:海马DG区ERS可能通过抑制CaMKII/ERK/BDNF通路损伤AD大鼠的空间学习和记忆功能。     

可乐定对慢性脑缺血大鼠学习记忆及ERK信号通路相关蛋白的影响

目的:研究可乐定(clonidine)对大鼠慢性脑缺血(ischemia)后认知功能的影响并初步探讨其神经保护作用机制。方法:将45只SD大鼠随机分为假手术(sham)组、脑缺血(ischemia)组和可乐定(clonidine)组,每组15只。通过大脑中动脉栓塞法建立慢性脑缺血大鼠模型。各组大鼠在术前1周连续灌胃给药,其中clonidine组每日以clonidine 100μg/kg灌胃,sham组和ischemia组以等体积蒸馏水灌胃。术后4周,用Morris水迷宫法检测各组大鼠的学习记忆能力,免疫组织化学法和Western blot法检测非磷酸化和磷酸化细胞外信号调节激酶1/2(ERK1/2)及环磷腺苷效应元件结合蛋白(CREB)的蛋白水平。结果:Morris水迷宫实验结果显示,与假手术组相比,脑缺血组大鼠学习和记忆能力减弱;与脑缺血组相比,可乐定组大鼠学习和记忆能力增强。免疫组织化学法和Western blot法检测结果表明,与假手术组比较,脑缺血组大鼠海马组织中p-ERK1/2和CREB的蛋白水平均增加(P0.01);与脑缺血组相比,可乐定组大鼠海马组织中p-ERK1/2和p-CREB的蛋白水平降低(P0.01)。结论:可乐定可能通过调节ERK信号通路相关蛋白ERK1/2和CREB的表达,从而改善脑缺血再灌注引起的学习记忆障碍。     

合欢花水提物对抑郁模型大鼠学习记忆及海马CREB表达的影响

目的:观察合欢花水提物对抑郁模型大鼠学习记忆能力及海马CREB表达的影响。方法:SD大鼠40只,随机分为空白组、模型组、氟西汀组和合欢花组,每组10只。采用孤养加慢性轻度不可预见性应激结合方法构建抑郁模型,氟西汀或合欢花水提物灌胃治疗21 d。空白组给予生理盐水。用药结束后,采用体重测定、旷场试验、糖水实验评估各组大鼠的抑郁情况。Morris水迷宫测试各组大鼠的学习记忆能力。ELISA法检测海马组织中cAMP含量。免疫组化法检测海马CREB的表达情况。结果:与模型组相比,合欢花组和氟西汀组抑郁症状明显改善。水迷宫结果显示:与空白组比较,模型组大鼠的逃避潜伏期(EL)明显延长,平台所在象限的游泳时间百分比和穿越站台次数明显减少(P0.01);与模型组比较,氟西汀组和合欢花组EL明显缩短,游泳时间百分比和穿越站台次数增加(P0.05或P0.01);但氟西汀组和合欢花组以上指标的差异不明显(P0.05)。海马cAMP含量及CREB平均光密度检测结果显示:与空白组比较,模型组大鼠海马cAMP含量、CREB的平均光密显著降低(P0.01);与模型组相比,氟西汀组和合欢花组上述指标明显升高(P0.01);而氟西汀组和合欢花组上述指标无统计学差异(P0.05)。结论:合欢花水提物可以改善抑郁模型大鼠的抑郁症状提高抑郁大鼠学习记忆能力,其机制可能与提高海马CREB的表达影响cAMP-CREB通路有关。     

硫酸茯苓多糖对抑郁症大鼠海马AMPA受体表达的影响

目的:探讨硫酸茯苓多糖(SP)是否通过调节AMPA受体GluR1的表达而生产抗抑郁作用。方法:实验设假手术组、抑郁症模型组、SP(25、50、100 mg/kg)三个给药组及SP(100 mg/kg)+AMPA受体抑制剂GYKI 52466组,每组动物12只。抑郁症动物模型采用卵巢摘除加慢性不可预知性温和应激(CUMS)法制备。连续灌胃和(或)腹腔注射给药21天。糖水消耗、强迫游泳及敞箱试验观察动物行为变化。海马神经元病理变化采用尼氏染色法检测。GluR1、p-GluR1、CREB、p-CREB和BDNF的蛋白表达采用免疫组化和(或)Western Blot法检测。结果:与模型组相比,SP各组大鼠强迫游泳不动时间(FSIT)明显降低而自发活动(SA)明显增加、糖水摄入量(SC)及糖水偏爱百分比(PSC)明显升高(P0.05或P0.01)、海马神经元损伤显著减轻、GluR1和GluR1磷酸化水平及p-CREB、BDNF的表达均明显升高。但与SP(100 mg/kg)剂量组相比,SP+GYKI 52466剂量组大鼠FSIT又明显增加而SA又明显减少,SC及PSC又明显降低,海马GluR1、p-GluR1及p-CREB、BDNF的表达又明显降低(P0.01)。结论:SP可能通过上调海马GluR1受体的表达,增强GluR1受体功能,促使CREB磷酸化水平升高而上调BDNF的蛋白表达而产生抗抑郁作用。     

可卡因－苯丙胺调节转录肽激活ERK促进海马神经元合成BDNF

目的： 探讨细胞外信号调节激酶(ERK)通路在可卡因－苯丙胺调节转录肽（CART）上调大鼠海马神经元脑源性神经营养因子（BDNF）表达中的作用。方法： 取18 d的SD大鼠胚胎（E18），分离海马神经元,体外原代培养7 d，以不同剂量CART处理细胞，用Western blotting方法分别检测不同处理时点p-ERK表达。再以ERK通路特异性阻断剂PD98059（25 μmol/L）预处理细胞，进一步观察CART对p-ERK表达及BDNF合成的影响。 结果： 同对照组比较，CART处理组海马神经元p-ERK表达明显增高（P<0.01），BDNF合成增加。PD98059能阻断内源性ERK磷酸化、也能阻断CART诱导的ERK磷酸化，同时抑制CRAT引起的BDNF合成。结论： CART通过激活ERK促进海马神经元BDNF的合成，从而发挥神经营养作用。     

GLYX-13 通过NR2B-ERK-CREB 信号通路改善氯胺酮麻醉后幼鼠认知 功能障碍

目的:探讨GLYX-13通过N-甲基-D-门冬氨酸受体2B(NR2B)-胞外信号调节激酶(ERK)-环磷腺苷效应元件结合蛋白(CREB)信号通路改善氯胺酮麻醉后幼鼠认知功能障碍。方法:将60只幼鼠根据随机数字法分为对照组(NS组)、氯胺酮麻醉组(Ket组)、氯胺酮麻醉+GLYX-13组(Ket+GLYX-13组),每组20只。Ket组和Ket+GLYX-13组小鼠每天腹腔注射30 mg/kg氯胺酮,间隔30 min重复一次,每天3次;Ket+GLYX-13组小鼠每天首次注射氯胺酮前2 h尾静脉注射1 mg/kg GLYX-13;NS组每天注射等量生理盐水,共5 d。水迷宫实验和旷场实验测定小鼠认知功能,Western blot法测定海马组织NR2B、ERK、磷酸化ERK(p-ERK)、CREB、p-CREB蛋白水平,免疫荧光法测定海马CA1区NR2B、p-ERK、p-CREB蛋白表达情况。结果:与NS组比较,Ket组和Ket+GLYX-13组小鼠逃避潜伏期延长(P0.05),穿越原平台象限次数和在原平台象限停留时间降低(P0.05),中心区停留时间均缩短(P0.05),海马组织NR2B、p-ERK、p-CREB蛋白水平降低(P0.05),海马CA1区NR2B、p-ERK、p-CREB荧光阳性信号强度降低(P0.05)。与Ket组比较,Ket+GLYX-13组小鼠逃避潜伏期缩短(P0.05),穿越原平台象限次数和在原平台象限停留时间升高(P0.05),中心区停留时间均延长(P0.05),海马组织NR2B、p-ERK、p-CREB蛋白水平升高(P0.05),海马CA1区NR2B、p-ERK、p-CREB荧光阳性信号强度升高(P0.05)。结论:GLYX-13通过激活NR2B-ERK-CREB信号通路改善氯胺酮麻醉后幼鼠认知功能障碍。     

电针对海洛因成瘾大鼠学习记忆及海马CREB表达的影响

目的：探讨电针对海洛因成瘾大鼠学习记忆的影响及作用机制。方法130只Wistar大鼠随机分为对照组、海洛因成瘾组（简称成瘾组）和海洛因成瘾后作电针治疗组（简称电针组）。进行跳台实验测试大鼠学习记忆能力,并用免疫组化方法检测鼠脑海马环磷酸腺苷反应元件结合蛋白（CREB）和磷酸化CREP（P—CREB）的表达。结果：成瘾组大鼠学习记忆下降（P％0．01）,电针组大鼠学习记忆有所改善（P〈0．01）;成瘾组大鼠海马CREB、P—CREB表达较对照组增高（P〈0．05）,电针组更高（P〈0．01）。结论：电针治疗可在一定程度上对抗海洛因成瘾大鼠所致的学习记忆下降,其机制可能与海马内CREB、P—CREB表达变化有关;CREB、PCREB参与学习记忆及海洛因成瘾的形成。     

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.     

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.     

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...