深低温体外循环对犬海马CA3区BDNF和CaBP表达的影响

目的研究深低温停循环时,不同脑保护方法对海马CA3区脑源性神经营养因子（BDNF）和钙结合蛋白（CaBP）表达的影响及意义。方法健康杂种犬18只,随机分为常温体外循环组（对照组）,深低温停循环组（DH-CA）,间断深低温停循环组（I-DHCA）,按临床方法建立体外循环。循环结束,取吻侧海马,经病理常规处理后,切片应用免疫组织化学染色方法观察海马CA3区BDNF和CaBP表达。结果DHCA组和I-DHCA组BDNF表达阳性细胞数多于对照组,差别有显著意义（P<0.01）,DHCA组表达显著多于I-DHCA组,差别有显著意义（P<0.01）。对照组和I-DHCA组CaBP蛋白表达阳性细胞数多于DHCA组,差别有显著意义（P<0.01）,对照组表达显著多于I-DHCA组,差别有显著意义（P<0.05）。结论I-DHCA脑保护效果优于DHCA,I-DHCA可以延长深低温停循环时限;BDNF和CaBP可能对减轻DHCA脑缺血缺氧损伤起重要作用。     

糖尿病大鼠脑葡萄糖转运子1和3蛋白表达随血糖浓度而变化

以Wistar大鼠建立链脲佐菌素糖尿病模型，用胰岛素使其血糖控制在〈10、10～14和〉16．7mmol／L3个不同水平，用免疫组化法检测对照组及3个糖尿病组大鼠大脑中葡萄糖转运蛋白（GLUT）1和3蛋白表达变化。结果发现慢性高血糖可引起脑内GLUT1和GLUT3蛋白表达降调节。     

类肌钙蛋白和钙调蛋白结合蛋白在胃肠运动及其病理适应性调节中的作用

目的;研究类肌钙蛋白（calponion,CaP)和钙调蛋白结合蛋白（caldesmon,CaD)在胃肠道中的表达及其在胃肠运动病理适应性调节中的作用。方法：通过建立慢性番泻叶诱导的胃肠运动增强和实验性肝硬化胃肠运动减弱2种动物模型,应用SDS－PAGE和Western blot方法检测不同胃肠运动状态下胃肠道平滑肌组织中CaP和CaD的表达,并用图像分析进行定量比较。结果：建立了慢性番泻叶诱导的胃肠运动增强和实验性肝硬化胃肠运动减弱2种动物模型。正常小鼠和大鼠胃肠道组织中CaP和CaD的含量依次为结肠＞胃＞小肠;慢性胃肠运动增强小鼠肠道组织中CaP和CaD的含量下降;实验性肝硬化胃肠运动减弱大鼠胃肠道组织中CaP和CaD的含量显著增加,而经左旋硝基精氨酸甲基酯治疗胃肠运动恢复后,它们的含量亦恢复至正常。结论：CaP和CaD的表达与胃肠道各部分的运动状态密切相关,胃肠道运动增强,其含量减少,胃肠道运动减弱则其表达增高。提示这2种蛋白质分子参与了胃肠运动的调节和病理适应性调节过程。     

甲状腺素对甲状腺功能减退症大鼠海马syntaxin-1蛋白表达的影响

目的 研究成年期甲状腺功能减退症(简称甲减)大鼠海马突触前膜蛋白syntaxin-1的表达及不同剂量甲状腺素替代治疗的作用,探讨甲减脑损伤可能的分子机制.方法 健康3月龄成年SD雄性大鼠44只,体质量250 ～ 300 g,按体质量随机分为4组:甲减组、常规治疗组、大剂量治疗组和对照组,每组11只.甲减组、常规治疗组和大剂量治疗组每日腹腔注射丙基硫氧嘧啶(PTU) 10 mg/kg;4周后,甲减组继续给予PTU腹腔注射2周,常规治疗组和大剂量治疗组每日分别给予50、200μg/kg左旋甲状腺素腹腔注射2周;对照组每日腹腔注射等量生理盐水.造模结束后,采用放射免疫法检测4组大鼠血清T3、T4水平;采用免疫组化法检测4组大鼠海马syntaxin-1蛋白的表达.结果 与对照组[(0.65±0.05)、(55.20±3.56)nmol/L]比较,甲减组血清T3、T4[(0.34±0.04)、(43.01±2.95)nmol/L]明显降低(P均＜0.05),大剂量治疗组血清T3、T4[(1.11±0.10)、(96.68±6.42)nmol/L]显著升高(P均＜0.05);常规治疗组血清T3、T4[(0.63±0.05)、(55.04±3.77)nmol/L]与对照组比较,差异无统计学意义(P均＞0.05).甲减组大鼠海马CA1、CA3区起始层、放射层、腔隙层和齿状回(DG)分子层、多形层syntaxin-1蛋白表达水平(0.059±0.016、0.064±0.014、0.068±0.016,0.069±0.017、0.072±0.016、0.070±0.011,0.051±0.012、0.072±0.017)显著高于对照组(0.037±0.008、0.045±0.010、0.042±0.009,0.040±0.010、0.053±0.009、0.042±0.009,0.032±0.007、0.047±0.010,P均＜0.05);常规治疗组和大剂量治疗组各层syntaxin-1蛋白表达水平(0.041±0.011、0.046±0.017、0.044±0.014,0.037±0.008、0.051±0.010、0.043±0.010,0.033±0.011、0.045±0.014和0.040±0.010、0.045±0.011、0.043±0.010,0.033±0.009、0.050±0.010、0.041±0.009,0.032±0.009、0.046±0.009)较甲减组降低(P均＜ 0.05),与对照组比较,差异无统计学意义(P均＞0.05).结论 成年期甲减大鼠海马内syntaxin-1蛋白表达增加,常规剂量甲状腺素替代治疗能使其恢复至正常水平.     

大鼠在空间辨别性学习记忆时海马CA3区星形胶质细胞的变化

目的观察大鼠在空间辨别性学习记忆时海马CA3区星形胶质细胞的变化,从而探讨星形胶质细胞与空间辨别性学习记忆的关系。方法以水迷宫法建立大鼠空间辨别性学习记忆动物模型,用星形胶质细胞GFAP免疫组织化学方法检测星形胶质细胞的数量和星形胶质细胞GFAP反应产物的AOD数值。结果具有空间辨别性学习记忆能力的大鼠海马星形胶质细胞的数量和星形胶质细胞GFAP反应产物的AOD数值均比对照组增加(P0.05)。结论星形胶质细胞参与空间辨别性学习记忆的过程,并与记忆的巩固有关。     

S100钙结合蛋白A12在炎症性肠病中的研究进展

S100钙结合蛋白A12（S100A12）是近年发现的S100蛋白家族成员,主要来源于中性粒细胞,具有促炎、调节免疫、抗微生物、参与信号转导等多种生物学功能,在多种炎症情况下表达明显增加。近年研究发现,炎症性肠病（IBD）患者的肠黏膜、血液和粪便S100A12含量均明显升高,由此提示其可作为本病诊断和鉴别诊断的指标之一,且可能在预测疾病活动度和治疗效果等方面具有重要作用。本文就S100A12在IBD中的研究进展作一综述。     

血吸虫钙结合蛋白研究进展

摘要 钙结合蛋白在生物机体中广泛存在,种类繁多,在生物体的生理活动及功能调节方面具有重要的作用,是血吸虫寄生于宿主不可或缺的蛋白。已报道的血吸虫钙结合蛋白有EF手家族及非EF手家族蛋白,它们都具有钙结合位点。在所报道的血吸虫钙结合蛋白中,很多都具有较好的免疫反应性,免疫动物后也具有较好保护性,例如Sm8、钙激活中性蛋白酶(calcium-activatedneutral proteinase,calpain)、Sm-p80、Sj22.6、Sm22.6、Sm20.8、SmIrV1、SjIrV1。血吸虫钙结合蛋白有可能是筛选疫苗候选分子的重要领域。     

钙卫蛋白在大肠癌中的表达及意义

目的研究钙卫蛋白(calprotectin)在大肠癌、大肠腺瘤、正常大肠黏膜中的表达情况。方法采取免疫组织化学法对大肠癌、大肠腺瘤、正常大肠黏膜标本中钙卫蛋白进行检测。结果钙卫蛋白在大肠癌细胞、大肠腺瘤细胞、正常大肠黏膜细胞中无表达,表达在以上组织间质的中性粒细胞中,癌组织中阳性率为75.61%,显著高于大肠腺瘤组织、正常结肠黏膜(4.87%、3.57%,P0.05);钙卫蛋白表达与大肠癌部位、病理类型、分化程度无关(P0.05)。结论大肠癌组织中钙卫蛋白含量增高,表达在大肠癌组织间质中。     

铝对大鼠海马细胞内钙水平和钙通道蛋白基因表达的影响

目的 观察铝对大鼠海马细胞内游离钙([Ca2+]i)水平和钙通道蛋白表达的影响.方法 以64只健康Wistar大鼠为研究对象,按体质量将大鼠分为16组,经口灌胃给予氯化铝(AlCl3),按AlCl3剂量(mg/kg)分为O(对照)、37.3、74.7、248.7组;染铝时间为45、75、120 d,其中120 d的大鼠再正常饲养30 d;分别在实验45、75、120、150 d处死大鼠,取脑分离海马.应用荧光分光光度计测定海马[Ca2+]i,应用RT-PCR方法检测海马中Ryanodine受体2(RyR2)和L-型钙通道α1C亚基(L-Ca2+α1C)mRNA表达情况.结果 AlCl3剂量和实验时间均可增加大鼠海马[Ca2+],(F值分别为23.136、19.089,P<0.01),二者具有交互作用(F=2.270,P<0.05);实验120、150 d时,大鼠海马[Ca2+]i,37.3、74.7、248.7 mg/kg组[(299.3±48.7)、(342.7±35.3),(391.2±47.9)、(408.1±42.8),(397.9±55.8)、(405.2±22.7)nmol/L]均较对照组[(195.1±29.9)、(209.1±30.6)nmol/L]明显升高(P<0.01).AlCl3可使大鼠海马RyR2、L-Ca2+α1C mRNA表达增加(F值分别为23.301、60.812,P<0.01).实验时间对大鼠海马中RyR2 mRNA表达无影响(F=1.361,P>0.05),但可下调L-Ca2+α1CmRNA的表达(F=6.088,P<0.01);AlCl3剂量和实验时间对L-Ca2+α1C mRNA表达有交互作用(F=5.876,P<0.01).实验75、120、150 d时,大鼠海马L-Ca2+α1C mRNA表达水平74.7、248.7 mg/kg组(1.03±0.16、1.18±0.18、0.92±0.11,1.89±0.26、1.25±0.10、1.07±0.14)均较同时间对照组(0.63±0.09、0.78±0.16、0.69±0.11)明显增加(P<0.05或<0.01).实验45、75、120、150 d时,大鼠海马RyR2 mRNA表达水平,74.7、248.7ms/kg组(0.49±0.06、0.51±0.07、0.57±0.11、0.47±0.11,0.47±0.03、0.52±0.09、0.70±0.10、0.78±0.09)均较同时间对照组组(0.24±0.07、0.32±0.04、0.30±0.06、0.27±0.06)明显升高(P<0.05或<0.01).结论 铝可以通过上调RyR2 mRNA和L-Ca2+α1C mRNA的表达而增加海马[Ca2+]i,发挥不可恢复性的神经毒性作用.     

5-羟色胺在大鼠海马CA1、CA2、CA3脑区的分布与表达

目的通过观察5-羟色胺(5-HT)在海马神经环路的分布和表达,为研究5-HT参与学习记忆的作用机制提供形态学依据。方法采用免疫组织化学技术观测抗5-HT的抗体阳性神经元在海马CA1、CA2和CA3区的分布特征。结果①抗5-HT的抗体在海马CA1、CA2和CA3的细胞中广泛分布。②海马中分子层阳性细胞数较少,排列不规则。锥体层细胞从内到外排列整齐,密集成带,染色强烈。多形层细胞染色细胞散在分布。③空白对照切片未见抗5-HT抗体的阳性神经元胞体。结论 5-HT在大鼠海马分布广泛,可能参与了海马学习记忆有关的过程。     

Deficits in memory and hippocampal long-term potentiation in mice with reduced calbindin D28K expression.

The influx of calcium into the postsynaptic neuron is likely to be an important event in memory formation. Among the mechanisms that nerve cells may use to alter the time course or size of a spike of intracellular calcium are cytosolic calcium binding or "buffering" proteins. To consider the role in memory formation of one of these proteins, calbindin D28K, which is abundant in many neurons, including the CA1 pyramidal cells of the hippocampus, transgenic mice deficient in calbindin D28K have been created. These mice show selective impairments in spatial learning paradigms and fail to maintain long-term potentiation. These results suggest a role for calbindin D28K protein in temporally extending a neuronal calcium signal, allowing the activation of calcium-dependent intracellular signaling pathways underlying memory function.     

Regulation of excitatory transmission at hippocampal synapses by calbindin D28k.

Distinct subpopulations of neurons in the brain contain one or more of the Ca(2+)-binding proteins calbindin D28k, calretinin, and parvalbumin. Although it has been shown that these high-affinity Ca(2+)-binding proteins can increase neuronal Ca2+ buffering capacity, it is not clear which aspects of neuronal physiology they normally regulate. To investigate this problem, we used a recently developed method for expressing calbindin D28k in the somatic and synaptic regions of cultured hippocampal pyramidal neurons. Ninety-six hours after infection with a replication-defective adenovirus containing the calbindin D28k gene, essentially all cultured hippocampal pyramidal neurons robustly expressed calbindin D28k. Our results demonstrate that while calbindin D28k does not alter evoked neurotransmitter release at excitatory pyramidal cell synapses, this protein has a profound effect on synaptic plasticity. In particular, we show that calbindin D28k expression suppresses posttetanic potentiation.     

Local generation of multineuronal spike sequences in the hippocampal CA1 region

Sequential activity of multineuronal spiking can be observed during theta and high-frequency ripple oscillations in the hippocampal CA1 region and is linked to experience, but the mechanisms underlying such sequences are unknown. We compared multineuronal spiking during theta oscillations, spontaneous ripples, and focal optically induced high-frequency oscillations (“synthetic” ripples) in freely moving mice. Firing rates and rate modulations of individual neurons, and multineuronal sequences of pyramidal cell and interneuron spiking, were correlated during theta oscillations, spontaneous ripples, and synthetic ripples. Interneuron spiking was crucial for sequence consistency. These results suggest that participation of single neurons and their sequential order in population events are not strictly determined by extrinsic inputs but also influenced by local-circuit properties, including synapses between local neurons and single-neuron biophysics.A hypothesized hallmark of cognition is self-organized sequential activation of neuronal assemblies (1). Self-organized neuronal sequences have been observed in several cortical structures (2–5) and neuronal models (6–7). In the hippocampus, sequential activity of place cells (8) may be induced by external landmarks perceived by the animal during spatial navigation (9) and conveyed to CA1 by the upstream CA3 region or layer 3 of the entorhinal cortex (10). Internally generated sequences have been also described in CA1 during theta oscillations in memory tasks (4, 11), raising the possibility that a given neuronal substrate is responsible for generating sequences at multiple time scales. The extensive recurrent excitatory collateral system of the CA3 region has been postulated to be critical in this process (4, 7, 12, 13).The sequential activity of place cells is “replayed” during sharp waves (SPW) in a temporally compressed form compared with rate modulation of place cells (14–20) and may arise from the CA3 recurrent excitatory networks during immobility and slow wave sleep. The SPW-related convergent depolarization of CA1 neurons gives rise to a local, fast oscillatory event in the CA1 region (“ripple,” 140–180 Hz; refs. 8 and 21). Selective elimination of ripples during or after learning impairs memory performance (22–24), suggesting that SPW ripple-related replay assists memory consolidation (12, 13). Although the local origin of the ripple oscillations is well demonstrated (25, 26), it has been tacitly assumed that the ripple-associated, sequentially ordered firing of CA1 neurons is synaptically driven by the upstream CA3 cell assemblies (12, 15), largely because excitatory recurrent collaterals in the CA1 region are sparse (27). However, sequential activity may also emerge by local mechanisms, patterned by the different biophysical properties of CA1 pyramidal cells and their interactions with local interneurons, which discharge at different times during a ripple (28–30). A putative function of the rich variety of interneurons is temporal organization of principal cell spiking (29–32). We tested the “local-circuit” hypothesis by comparing the probability of participation and sequential firing of CA1 neurons during theta oscillations, natural spontaneous ripple events, and “synthetic” ripples induced by local optogenetic activation of pyramidal neurons.     

Calbindin D28k对帕金森病模型小鼠纹状体凋亡相关蛋白表达的影响

目的观察1-甲基4-苯基1,2,3,6四氢吡啶(MPTP)致帕金森病(PD)模型小鼠黑质多巴胺能神经细胞过表达Calbindin D28k(CB)时,纹状体细胞抗损伤作用机制。方法选择C57BL/6小鼠连续5 d腹腔注射MPTP,构建成功PD模型小鼠30只,随机分为模型组,人类免疫缺陷病毒(HIV)Ⅰ组(注射HIV Ⅰ)和CB-HIV-Ⅰ组(注射CB-HIV-Ⅰ),每组10只,连续6周对各组小鼠行为学检测,Western blot法检测各组小鼠CB,Bcl 2和Bax的表达变化。结果与模型组和HIV-Ⅰ组比较,CB-HIV-Ⅰ组小鼠各时间点移动格子次数,第1、2、5和6周站立次数,第6周时游泳和悬挂时间,差异有统计学意义(P0.05,P0.01);CB-HIV Ⅰ组小鼠中脑黑质中CB的表达量显著升高(P0.05),纹状体细胞中Bcl-2的表达量亦明显升高(P0.01),而Bax的表达量明显降低(P0.01)。模型组和HIV-Ⅰ组上述指标差异无统计学意义(P0.05)。结论黑质多巴胺能神经细胞过表达CB时,纹状体细胞Bcl-2/Bax表达上调,提示其与纹状体细胞抗凋亡能力增强有关。     

TPA decreases 1,25(OH)2D3 binding and calbindin D-28K in renal (MDBK) cells.

The effect of the phorbol ester TPA (12-O-tetradecanoylphorbol 13-acetate) on vitamin D receptors (VDRs) was studied in MDBK cells, a normal bovine renal epithelial cell line. 24 h treatment of MDBK cells with TPA resulted in down-regulation of VDR number, with no change in the binding affinity for 1,25-dihydroxyvitamin D3 (1,25(OH)2D3) or approximate molecular weight determined by fast protein liquid chromatography (FPLC). TPA treatment also reduced the level of calbindin D-28K, a vitamin D-dependent renal protein. 4 alpha-Phorbol 12,13-didecanoate (4 alpha-PDD), an inactive phorbol ester, did not affect either 1,25(OH)2D3 binding or calbindin D-28K levels. TPA elicited a significant decrease in membrane-associated protein kinase C (PKC) activity which coincided with the reduction in VDR number and calbindin D-28K. These data support a link between TPA, PKC activity and vitamin D actions in kidney.     

电针对衰老模型大鼠学习记忆及海马CA1区LTP的影响

目的 研究电针对D-半乳糖致衰老大鼠学习记忆障碍和海马CA1区突触传递长时程增强(LTP)效应的影响,探索电针改善学习和记忆的作用机制.方法 将SD大鼠随机分为正常对照组、模型组和电针组.采用腹腔注射D-半乳糖的方法建立衰老大鼠模型;电针组选取百会和足三里穴给予大鼠电针治疗,参数设定为:3 Hz,1 mA,连续波.采用Morris水迷宫观察大鼠行为学变化;并采用高频刺激Schaffer侧支,然后在同侧海马CA1区诱导LTP的方法检测大鼠海马突触可塑性的变化.结果 模型组与正常对照组相比水迷宫测试中的逃避潜伏期明显延长,距离百分比明显降低(P＜0.05,P＜0.01);而电针组与模型组相比潜伏期明显缩短,距离百分比明显增大(P＜0.01).模型组与正常对照组相比海马CA1区LTP明显受到抑制(P＜0.01),而电针组能减轻D-半乳糖对海马CA1区LTP的抑制作用,明显改善突触功能的可塑性(P＜0.05).结论 电针可改善由D-半乳糖致衰老大鼠学习记忆能力,其作用机制之一可能与大鼠海马CA1区LTP的提高有关.     

Topographic specificity of functional connections from hippocampal CA3 to CA1

The hippocampus is a cortical region thought to play an important role in learning and memory. Most of our knowledge about the detailed organization of hippocampal circuitry responsible for these functions is derived from anatomical studies. These studies present an incomplete picture, however, because the functional character and importance of connections are often not revealed by anatomy. Here, we used a physiological method (photostimulation with caged glutamate) to probe the fine pattern of functional connectivity between the CA3 and CA1 subfields in the mouse hippocampal slice preparation. We recorded intracellularly from CA1 and CA3 pyramidal neurons while scanning with photostimulation across the entire CA3 subfield with high spatial resolution. Our results show that, at a given septotemporal level, nearby CA1 neurons receive synaptic inputs from neighboring CA3 neurons. Thus, the CA3 to CA1 mapping preserves neighbor relations.