Expression of Vascular Endothelial Growth Factor-C and Vascular Endothelial Growth Factor Receptor-3 in Ovarian Epithelial Tumors

Objective： To explore the role of vascular endothelial growth factor-C （VEGF-C） in the process of angiogenesis, lymphangiogenesis and lymphatic metastasis in epithelial ovarian tumors. Methods： In situ hybridization and immunohistochemical staining for VEGF-C were performed in 30 epithelial ovarian carcinomas, 9 borderline tumors and 26 benign tumors. Endothelial cells were immunostained with anti-VEGFR-3 pAb and anti-CD31 mAb, and VEGFR-3 positive vessels and microvessel density （MVD） were assessed by image analysis. Results： VEGF-C mRNA and protein expression were detected in cytoplasm of carcinoma cells. VEGF-C mRNA and protein expression in ovarian epithelial carcinomas were significantly higher than those in borderline tumors and benign tumors （P〈0.05 or P〈0.01）. In ovarian epithelial carcinomas, VEGF-C protein expression, VEGFR-3 positive vessels and MVD were significantly higher in the cases of clinical stage Ⅲ-Ⅳ and with lymph node metastasis than those of clinical stage Ⅰ-Ⅱ and without lymph node metastasis respectively （P〈0.05 or P〈0.01）. VEGFR-3 positive vessels and MVD were significantly higher in VEGF-C protein positive tumors than negative tumors （P〈0.05）. VEGFR-3 positive vessels was significantly correlated with MVD（P〈0.01）. Conclusion： VEGF-C might play a role in lymphatic metastasis via lymphangiogenesis and angiogenesis in epithelial ovarian tumors, and VBEGF-C could be used as a biologic marker of metastasis in ovarian epithelial tumors.

Study on the Expression of Dopamine Receptor-3(DRD3) in Rats after Sacral Spinal Cord Transection

[Objectives] This study aimed to study the distribution characteristics of DRD3(dopamine receptor-3) and the changes in its expression before and after spinal cord injury(SCI), in order to lay a morphological basis for later research. [Methods] Adult male Wistar rats were randomly divided into sham operation group and SCI group. The rat spinal cord transection model at the sacral 2(S_2) segment was established. Rat tail spasticity score was performed 60 d after SCI, and the rats with 4-5 points were screened for perfusion. The expression of DRD3 in the sacral spinal cord(S+C segment) was detected by immunofluorescence. [Results] In normal rats, DRD3 was mainly distributed in the dorsal horn(DH), intermediate zone(IMZ) and ventral horn(VH) of the gray matter. It was also expressed in the white matter of the spinal cord. After SCI, the distribution of DRD3 in the segment below the injury section was similar to that of normal rats. However, the expression was different(P<0.05). [Conclusions] There was no significant change in the distribution of DRD3 in spinal cord after SCI. After the spinal cord S_2 was completed transected, the expression of DRD3 was significantly reduced in the DH, IMZ and VH regions of the gray matter of the spinal cord.

细胞钙离子转运蛋白兰尼碱受体3与ApoE基因敲除小鼠动脉粥样硬化斑块形成的关系

目的:观察细胞钙离子转运蛋白兰尼碱受体3(ryanodine receptor 3,RYR3)在动脉粥样硬化斑块形成过程中的改变,探讨两者的相关性。方法:选取6周龄雄性载脂蛋白E基因敲除(ApoE-/-)小鼠及野生型C57BL/6J小鼠,高脂饲喂20、27和33周后,在各个时点处死动物取主动脉根部制作连续切片。(1)HE染色,观察组织形态学的变化,计算机图像分析仪测量斑块面积和血管管腔面积,计算校正斑块面积(斑块面积/血管管腔面积)。(2)免疫组织化学染色,计算机图像分析仪测定不同周龄小鼠细胞钙离子转运蛋白RYR3表达变化。结果:与同周龄对照组小鼠相比,ApoE-/-小鼠体内RYR3表达显著减少(P<0.05),随着ApoE-/-小鼠周龄的增加,RYR3的表达明显减少,且与斑块面积/血管管腔面积呈负相关(r=-0.652,P<0.01)。结论:细胞钙离子转运蛋白RYR3参与动脉粥样硬化的病理过程,且与动脉粥样硬化斑块的形成密切相关。

雌激素对大鼠阴道平滑肌细胞兰尼碱受体1和L-型钙通道V1.3表达的影响

目的:研究卵巢去势大鼠阴道平滑肌中兰尼碱受体1(RyR1)和L-型钙通道V1.3(Cav1.3)的表达,以探讨RyR1和Cav1.3与雌激素在女性性功能障碍中的相关性。方法:40只8周龄雌性SD大鼠随机均分成:假手术2周组(A组)、假手术4周组(B组)、去势2周组(C组)和去势4周组(D组)。术后2、4周运用全自动化学发光免疫法测定各组大鼠血清雌激素水平,RT-PCR和免疫组化法检测阴道平滑肌中RyR1和Cav1.3的mRNA及其蛋白表达。灰度比值表示RyR1和Cav1.3的mRNA表达量,积分光密度值表示RyR1和Cav1.3蛋白表达量。结果:血清雌激素水平C组[(0.210±0.026)nmol/L]较A组[(0.505±0.053)nmol/L]显著降低(P<0.01),D组[(0.130±0.031)nmol/L]较B组[(0.476±0.058)nmol/L]显著降低(P<0.01)。RyR1和Cav1.3在各组大鼠阴道平滑肌内均有表达。RyR1mRNA灰度比值C组(0.680±0.073)较A组(0.950±0.064)显著降低(P<0.01),D组(0.220±0.032)较B组(0.890±0.072)显著降低(P<0.01);Cav1.3mRNA灰度比值C组(0.580±0.043)较A组(0.870±0.019)显著降低(P<0.01),D组(0.190±0.020)较B组(0.820±0.021)显著降低(P<0.01)。RyR1蛋白表达积分光密度值C组(96.67±7.75)较A组(123.69±10.66)显著降低(P<0.01),D组(86.45±8.16)较B组(109.31±9.87)显著降低(P<0.01);Cav1.3蛋白表达积分光密度值C组(87.97±6.96)较A组(106.46±8.04)显著下降(P<0.01),D组(69.43±8.30)较B组(97.38±7.56)显著降低(P<0.01)。结论:RyR1和Cav1.3在大鼠阴道平滑肌内均有表达,雌激素可能通过影响大鼠阴道平滑肌中RyR1和Cav1.3的表达参与女性性反应调控。

高血压患者RYR-3基因多态性与大动脉粥样硬化性卒中的相关性研究

目的:探讨中国北方汉族人群中,高血压患者兰尼碱受体-3(RYR-3)基因多态性与大动脉粥样硬化性卒中的关系。方法:选择高血压合并大动脉粥样硬化性卒中患者232例为卒中组,高血压非卒中且不伴有颈动脉狭窄的患者200例为高血压组,非高血压健康体检者200例为对照组,采用基质辅助激光解吸电离飞行时间质谱法比较RYR-3基因型多态性在各组间的差异。结果:卒中组RYR-3基因rs877087位点基因型和等位基因与高血压组比较,差异均无统计学意义(均P>0.05);卒中组和对照组的基因型和等位基因的差异均有统计学意义(均P<0.05)。卒中组RYR-3基因rs2229116位点基因型和等位基因与高血压组比较,差异均有统计学意义(均P<0.05)。多因素Logistic回归分析结果显示RYR-3基因rs2229116基因型AA是高血压患者发生LAA的危险因素(OR=1.155,95%CI 1.018-1.626,P=0.030)。结论:对于高血压患者,RYR-3基因rs2229116位点多态性与大动脉粥样硬化性卒中密切相关。

bFGF对人晶状体上皮细胞系内钙离子及IP3R、RyR的作用

目的:探讨碱性成纤维细胞生长因子(bFGF)对人晶状体上皮细胞系LEC-B3内静息Ca2+浓度及三磷酸肌醇受体(IP3R)、ryanodine受体(RyR)表达的影响。方法:LEC-B3细胞系传代培养,分别以1,10,100μg/L bFGF诱导第3代细胞的增殖,MTT法检测其增殖度,激光扫描共聚焦显微镜测细胞内静息钙浓度;RT-PCR(reverse-transcriptase,PCR)方法检测10μg/L bFGF作用后细胞内IP3R和RyRmRNA的表达。结果:与对照组相比,3个浓度的bFGF对LEC-B3都有促增殖作用(P<0.01),其中10μg/L作用最强;bFGF作用后细胞内Ca2+浓度呈bFGF浓度依赖性增高,10μg/L,100μg/LP<0.01,1μg/L<0.05;10μg/L bFGF作用后的细胞IP3RI mRNA表达无明显变化,III型表达明显减弱(P<0.01),ryan-odineRI,IIImRNA表达升高(P<0.05,0.01)。结论:bFGF诱导LEC-B3细胞增殖引起细胞内钙离子浓度增加。Ca2+升高呈bFGF浓度依赖性,并不与细胞增殖度平行。bFGF对IP3R和RyR亚型的mRNA表达有一定影响,并且细胞内Ca2+浓度升高与bFGF刺激RyRmRNA表达升高有关。

Pioglitazone ameliorates retinal ischemia/reperfusion injury via suppressing NLRP3 inflammasome activities

AIM：To explore the role of Pioglitazone（Pio） on a mouse model of retinal ischemia/reperfusion（I/R） injury and to elucidate the potential mechanism.METHODS：Retinal ischemia was induced in mice by increasing the intraocular pressure,and Pio was administered 4 h though periocular injection before I/R.The number of cells in the ganglion cell layer（GCL） was counted 7 d after retinal I/R injury.Glial fibrillary acidic protein（GFAP）,nuclear factor-kappa B（NF-κB）,p38,phosphorylated-p38,PPAR-γ,interleukin-1β（IL-1β）,Toll-like receptor 4（TLR4）,NLRP3,cleaved caspase-1,caspase-1 were determined by real-time polymerase chain reaction and Western blotting.RESULTS：Pio promoted the survival of retinal cells in GCL following retinal I/R injury（P〈0.05）.Besides,retinal I/R injury stimulated the expression of GFAP and TLR4,which were partially reversed by Pio treatment（P0.05）.Retinal I/R injury-upregulated expression of NLRP3,cleaved caspase-1,IL-1β was attenuated after Pio treatment（P〈0.05）.Moreover,I/R injury induced activation of NF-κB and p38 were inhibited by Pio treatment（P〈0.05）.CONCLUSION：Pio promotes retinal ganglion cells survival by suppressing I/R-induced activation of TLR4/NLRP3 inflammasomes via inhibiting NF-κB and p38 phosphorylation.

VEGF、VEGF-C和VEGFR-3蛋白表达增加与前列腺癌进展期的相关性研究(英文)

Aim： To investigate the differences in microvessel densities （MVD） and the expressions of vascular endothelial growth factor （VEGF）, VEGF-C and VEGF receptor-3 （VEGFR-3） between prostate cancer （PCa） tissues and adjacent benign tissues, and to explore the correlations among MVD, Jewett-Whitmore staging, Gleason scores and expressions of VEGF, VEGF-C and VEGFR-3 in the progression of PCa. Methods： An immunohistochemical approach was adopted to detect the expressions of CD34, VEGF, VEGF-C and VEGFR-3 in both cancer areas and peripheral benign areas of 71 primary prostatic adenocarcinoma specimens. A statistic analysis was then performed according to the experimental and clinic data. Results： Significantly upregulated expressions of VEGF, VEGF-C and VEGFR-3 were all found in malignant epithelium/cancer cells compared with adjacent benign epithelium （P 〈 0.01）. Patients in stage D had a significantly higher score than patients in stage A, B or C when comparing the expression of VEGF-C or VEGFR-3 in the tumor area （P 〈 0.01）. In addition, significant correlations were observed between Jewett-Whitmore staging and VEGF-C （rs = 0.738, P 〈 0.01）, clinical staging and VEGFR-3 （rs = 0.410, P 〈 0.01）, VEGF-C and Gleason scores （rs = 0.401, P 〈 0.01）, VEGFR-3 and Gleason scores （rs = 0.581, P 〈 0.001） and MVD and VEGF （rs = 0.492, P 〈 0.001）. Conclusion： Increased expressions of VEGF and VEGF-C were closely associ- ated with progression of PCa. The main contribution of increased VEGF expression for PCa progression was to upregulate MVD, which maintained the growth advantage of tumor tissue. However, the chief role of increased expressions of VEGF-C and VEGFR-3 was to enhance lymphangiogenesis and provide a main pathway for cancer cells to disseminate. （Asian J Androl 2006 Mar; 8： 169-175）

Serum VEGFR-3 and survival of advanced gastric cancer patients treated with FOLFOX

AIM: To explore if vascular endothelial growth factor receptor-3 (VEGFR-3) and carcinoembryonic antigen (CEA) can predict overall survival in advanced gastric cancer.METHODS: VEGFR-3 level was assessed by enzymelinked immunosorbent assay,and CEA was assessed by chemiluminescence immunoassay in the sera of 81 advanced gastric cancer patients before treatment with oxaliplatin plus 5-fluorouracil and folinic acid.RESULTS: Median survival time in patients with a low serum VEGFR-3 level was significantly longer than in those with a higher VEGFR-3 level (15.4 mo vs 7.7 mo,P < 0.001).Patients with a low CEA level had a longer survival than those with a higher CEA level (15.8 mo vs 8.6 mo,P < 0.001).Thirty-nine patients with low VEGFR-3 and low CEA levels had a median survival of 19.7 mo (P = 0.0006).The hazard ratio for patients with a high VEGFR-3 level was 2.443 (P = 0.002).CONCLUSION: High serum VEGFR-3 level is correlated significantly with poor survival.In patients with a high serum level of VEGFR-3,alternative chemotherapy regimens should be considered.

Expressions of Connexin and Par-3 in the Distal Margin of Rectal Cancer after Ultra-low Anterior Resection

This study examined the expression of connexin and protease-activated receptor 3 （par-3） in the distal resection margin of rectal cancer and the correlation of the expression of the two proteins with tumor relapse. A total of 40 patients with rectal cancer underwent ultra-low anterior resection with curved cutter stapler. The pathological specimens were divided into 3 groups in terms of sampling sites： tumor group, 2.0-cm group （in which the tissues were harvested 2.0 cm distal to the tumor tissues）, 3.0-cm group （in which the tissues were taken 3.0 cm away from the tumor tissues）. All the samples were pathologically observed and then measured for the expression of connexin and par-3 by employing immunohistochemistry and Western blotting. The operations in this series went uneventfully. No anastomotic stoma bleeding, stenosis and death occurred postoperatively. Histopathologically, in the tumor group, epithelial cells lost normal pattern of arrangement and polarity, and were loosely connected and even detached. In the 3.0-cm group, the epithelia had normal appearance, obvious cell polarity and essentially intact cell junction. Immunohistochemistry and Western blotting indicated that the 3.0-cm group had the strongest expression of connexin and par-3, and the expression in the 2.0-cm group and the tumor group was relatively weak. There existed significant difference in the expression of the two proteins among the three groups （P〈0.05 for all）. It was concluded that the down-regulated connexin and par-3 in the distal margin of rectal cancer tissues may indicate the progression of the disease and high likelihood of recurrence and metastasis. Although no tumor cells were found in the sections of the 2.0cm group, the decreased expression of connexin and par-3 may suggest the development of anaplasia and the increased odds of tumor relapse. Therefore, we are led to speculate that tumor resection only including 2.0 cm of unaffected rectum could not completely avoid the distant metastasis and local relapse.

IP_(3)R与RyR对新生大鼠心肌细胞钙振荡调控的研究

目的拟探讨新生期心肌细胞中肌浆网上两种主要的钙离子释放通道1,4,5-三磷酸肌醇受体(1,4,5-trisphosphate receptors,IP_(3)Rs)及雷诺丁受体(ryanodine receptors,RyRs)对细胞内钙振荡的调节作用。方法以体外培养原代新生SD大鼠心肌细胞为实验材料,通过钙离子指示剂fura-2荧光成像,分别利用IP_(3)Rs及RyRs通道的激动剂phenylephrine(PE)、caffeine,以及抑制剂2-APB和tetracaine作用于细胞,研究这两类通道对细胞内钙振荡信号的影响。结果培养的单层新生大鼠心肌细胞有自发的同步的钙振荡;PE处理使得钙振荡频率增加,而2-APB则抑制胞内钙振荡的频率,但它们对钙振荡幅度无明显影响;caffeine增加钙振荡频率但扰乱细胞跳动节律,而tetracaine则完全抑制心肌细胞的钙振荡信号,使细胞停止跳动。此外,应用PE分别作用于培养3 d、7 d及10 d的新生大鼠心肌细胞后,发现其对钙振荡频率的调增作用随培养时间增加而明显下降。结论新生大鼠心肌细胞内钙振荡频率主要受IP_(3)Rs调节,而RyRs是大量钙离子释放的主要通道,决定钙振荡的幅度。

Expression and reconstitution of the bioluminescent Ca2+reporter aequorin in human embryonic stem cells,and exploration of the presence of functional IP3 and ryanodine receptors during the early stages of their differentiation into cardiomyocytes

In order to develop a novel method of visualizing possible Ca^(2+) signaling during the early differentiation of h ESCs into cardiomyocytes and avoid some of the inherent problems associated with using fluorescent reporters, we expressed the bioluminescent Ca^(2+) reporter, apo-aequorin, in HES2 cells and then reconstituted active holo-aequorin by incubation with f-coelenterazine. The temporal nature of the Ca^(2+) signals generated by the holo-f-aequorin-expressing HES2 cells during the earliest stages of differentiation into cardiomyocytes was then investigated. Our data show that no endogenous Ca^(2+) transients(generated by release from intracellular stores) were detected in 1–12-day-old cardiospheres but transients were generated in cardiospheres following stimulation with KCl or Ca Cl_2, indicating that holo-f-aequorin was functional in these cells. Furthermore, following the addition of exogenous ATP, an inositol trisphosphate receptor(IP_3R) agonist, small Ca^(2+) transients were generated from day 1 onward. That ATP was inducing Ca^(2+) release from functional IP_3 Rs was demonstrated by treatment with 2-APB, a known IP_3 R antagonist. In contrast, following treatment with caffeine, a ryanodine receptor(Ry R) agonist, a minimal Ca^(2+) response was observed at day 8 of differentiation only. Thus, our data indicate that unlike Ry Rs, IP_3 Rs are present and continually functional at these early stages of cardiomyocyte differentiation.

哌替啶的舒血管作用及其机制

目的 :探讨哌替啶扩张血管导致低血压的机制。方法 :制备大鼠离体主动脉环 ,记录血管环张力 ,观察哌替啶对高钾和苯肾上腺素 (Ph E)预收缩血管的作用。结果 :哌替啶不影响血管的静止张力 ,但可对高钾和 Ph E诱导的收缩产生非内皮依赖的舒张作用 ,并呈剂量 -反应关系。哌替啶既不影响咖啡因诱导的血管收缩 ,也不改变钌红作用后对高钾诱导收缩的抑制作用。在无钙条件下 ,哌替啶仍能抑制 Ph E的收缩 ,也抑制后续加入钙后引发的收缩。结论 :哌替啶对高钾和 Ph E诱导的血管收缩有舒张作用 ,机制可能与其阻断细胞膜钙通道和抑制 IP3敏感钙池的钙释放有关。

细胞外Ca^(2+)对爪蟾脑片神经元微抑制性突触后电流的调制

应用盲法膜片钳全细胞记录技术,以爪蟾视顶盖神经元微抑制性突触后电流(miniature inhibitory postsyn-aptic currents,mIPSCs)为指标,观察了细胞外 Ca^(2+)对爪蟾脑片神经元突触后 mIPSC的调制。结果表明:用细胞外无钙或无钙含乙二醇双乙胺醚-N,N’-四乙酸(EGTA)(200 nmol/L-2mmol/L)溶液灌流,均可使mIPSCs的发放频率降低;非特异性钙离子拮抗剂氯化铬(100μmol/L)也可使mIPSCs的频率降低;内质网钙泵抑制剂thapsigargin (TG)以及内质网ryanodine受体(RyR)激动剂ryanodine均可使mIPSCs频率升高,内质网RyR拮抗剂普鲁卡因则可降低mIPSCs的频率;磷脂酶C抑制剂U73122也可降低mIPSCs的频率,对三磷酸肌醇(inositol,4,5-triphosphate,IP_3)水平有抑制作用的咖啡因亦可显著地降低mIPSCs,甚至完全抑制mIPSCs。从而表明:对突触前神经元及其末梢,细胞外钙离子可通过细胞膜上的钙通道进入细胞内,使细胞内钙浓度升高,突触前神经末梢释放出更多的神经递质,进而可能使突触后mIPSCs的频率增加;突触前细胞内钙储池上的RyR和IP_3R均可介导钙从其中释放,并也可使突触前细胞内的钙离子浓度升高,进而可能使突触后mIPSCs的发放频率增加。

心肌兴奋-收缩耦联在出生后哺乳动物发育中的变化

兴奋-收缩耦联是心肌收缩的关键机制,由于出生后早期未成熟心肌与成熟心肌结构组成存在极大差异,因此这两个阶段心肌兴奋-收缩耦联调控机制有很大的不同。虽然成年心肌兴奋-收缩耦联的机制已很清楚,但调控未成熟心肌此过程的机制则尚待阐明。对这种"未成熟机制"的深入了解对于小儿先天性心脏病的治疗有着不容忽视的指导意义。未成熟心肌不同于成熟心肌兴奋-收缩耦联过程之处主要是参与此过程的钙通道的差异,本文通过与成熟心肌细胞兴奋-收缩耦联机制的比较,综述未成熟心肌细胞在出生后发育过程中调控细胞内Ca2+的各种通道的表型变化以及参与心肌兴奋-收缩耦联过程的机制变化。

心肌细胞核Ca^(2+)库特点及其调节的离体研究

研究核外Ca^(2+)浓度对核Ca^(2+)的影响,及细胞核Ca^(2+)摄取和释放的关系,以探讨核Ca^(2+)转运的调节机制。采用差速离心和密度梯度离心法分离纯化心肌细胞核,以Fluo-4/AM荧光指示剂负载心肌细胞核,应用激光共聚焦扫描显微镜和荧光分光光度计进行观察和测定。结果显示,分离纯化的成年大鼠心肌细胞核内自由[Ca^(2+)]随着核外[Ca^(2+)]的增加而逐渐增加,孵育液[Ca^(2+)]为1000 nmol/L达高峰,但二者增加的程度并不一致,之后随核外[Ca^(2+)]浓度的增加而呈降低趋势。ATP和100—600nmol/L的核外游离Ca^(2+),使心肌细胞核显示核被膜腔Ca^(2+)荧光,ATP和1000nmol/L的核外游离Ca^(2+)则进一步引起核浆内的Ca^(2+)荧光强度升高。荧光染色观察可见IP_3受体染色主要位于核内膜,而钙泵和ryanodine受体染色主要位于核外膜。IP_3和Ryancodine使核Ca^(2+)短暂升高1.68倍和1.93倍(P<0.001),而钙泵抑制剂Thapsigargin和IP_3受体抑制剂Heparin则分别使核Ca^(2+)降低64%和35.6%(p<0.05)。ryanodine使IP_3升高的核Ca^(2+)显著回落至正常水平以下(p<0.001)。Thapsigargin不能阻断IP_3和Ryanodine所致的核Ca^(2+)释放增加(p<0.05),但事先采用钙泵抑制剂Thapsigargin预处理心肌细胞核,则能显著的阻断IP_3和Ryanodine所致的核Ca^(2+)升高作用(Ca^(2+)释放作用)(p<0.05)。结果提示大鼠心肌细胞核可能也是细胞内的钙库之一,心肌细胞核上存在Ca^(2+)-ATPase、ryanodine受体和IP_3受体等Ca^(2+)转运系统,可能参与核Ca^(2+)摄取和释放的调节。

麻醉药对[Ca2＋]i的多途径改变及相关生物学效应

Ca2＋是细胞内的第二信使．它参与细胞内很多生理活动过程．包括神经递质释放．肌肉收缩，腺体分泌．学习记忆及细胞凋亡等。麻醉药可以通过多种方式直接或间接改变[Ca2＋]i从而对生物体产生错综复杂的影响．这些影响有些与麻醉作用有关有些与麻醉作用无关。

阿尔茨海默病与内质网Ca^2+紊乱的研究进展

阿尔茨海默病(Alzheimer’s disease,AD)是一种以学习记忆能力障碍为主要表现的渐进性神经系统退行性疾病,主要累及患者的海马体和大脑皮质区。AD的主要病理特点是该病患者脑内普遍的神经元凋亡、大脑皮质内出现神经原纤维缠结(neurofibrillary tangles,NFTs)和老年斑(senile plaque,SP)。据报道,世界上每3 s就会出现一个该病患者[1],然而令人惋惜的是至今尚无有效缓解和完全治愈的药物问世。其发病机制复杂,目前为大多数学者所认可的假说主要有:遗传学因素、Aβ学说、兴奋性氨基酸毒性作用、钙离子(Ca^2+)稳态失调、胰岛素相关代谢异常、中枢胆碱能系统受损、微管相关蛋白异常学说、自由基与氧化应激、炎症与免疫机制等,其中Ca^2+失调假说受到广泛关注,该假说提出在AD发病早期Ca^2+失调使得细胞信号通道异常进而造成细胞功能瘫痪,导致突触传递功能障碍和神经元受损。本文将对这一假说延伸的新型预防或治疗性药物的机制及其临床指导价值做一综述。

Distribution and localization of fibroblast growth factor-8 in rat brain and nerve cells during neural stem/progenitor cell differentiation

The present study explored the distribution and localization of fibroblast growth factor-8 and its potential receptor, fibroblast growth factor receptor-3, in adult rat brain in vivo and in nerve cells during differentiation of neural stem/progenitor cells in vitro. Immunohistochemistry was used to examine the distribution of fibroblast growth factor-8 in adult rat brain in vivo. Localization of fibroblast growth factor-8 and fibroblast growth factor receptor-3 in cells during neural stem/progenitor cell differentiation in vitro was detected by immunofluorescence. Flow cytometry and immunofluorescence were used to evaluate the effect of an anti-fibroblast growth factor-8 antibody on neural stem/progenitor cell differentiation and expansion in vitro. Results from this study confirmed that fibroblast growth factor-8 was mainly distributed in adult midbrain, namely the substantia nigra, compact part, dorsal tier, substantia nigra and reticular part, but was not detected in the forebrain comprising the caudate putamen and striatum. Unusual results were obtained in retrosplenial locations of adult rat brain. We found that fibroblast growth factor-8 and fibroblast growth factor receptor-3 were distributed on the cell membrane and in the cytoplasm of nerve cells using immunohistochemistry and immunofluorescence analyses. We considered that the distribution of fibroblast growth factor-8 and fibroblast growth factor receptor-3 in neural cells corresponded to the characteristics of fibroblast growth factor-8, a secretory factor. Addition of an anti-fibroblast growth factor-8 antibody to cultures significantly affected the rate of expansion and differentiation of neural stem/progenitor cells. In contrast, addition of recombinant fibroblast growth factor-8 to differentiation medium promoted neural stem/progenitor cell differentiation and increased the final yields of dopaminergic neurons and total neurons. Our study may help delineate the important roles of fibroblast growth factor-8 in brain activities and neural stem/progenitor cell differentiation.