脑卒中后抑郁大鼠丘脑脑源性神经营养因子及酪氨酸激酶受体B蛋白的表达变化

目的探讨脑卒中后抑郁(PSD)大鼠丘脑脑源性神经营养因子(BDNF)及其高亲和力受体酪氨酸激酶受体B(TrkB)蛋白的表达变化,及其在PSD发病机制中的作用和意义。方法选择成年SD大鼠24只,随机分为对照组、抑郁组、脑卒中组和模型组,每组6只。利用线栓法建立局灶性脑缺血大鼠模型,加以慢性不可预见的中等应激刺激和孤养方法造成PSD动物模型,应用免疫组织化学方法检测各组大鼠造模后第29天丘脑BDNF和TrkB免疫阳性细胞数的表达变化。结果模型组BDNF阳性细胞表达较对照组和抑郁组明显减少,差异有统计学意义(P<0.05);模型组TrkB阳性细胞表达较对照组、脑卒中组和抑郁组明显减少,差异有统计学意义[(9.00±2.12)个vs(41.22±11.91)个、(17.22±5.76)个和(33.67±8.32)个,P<0.01]。结论 PSD大鼠丘脑BDNF及其高亲和力受体TrkB蛋白表达减少可能与PSD发病机制有相关性。     

脑卒中后抑郁大鼠海马小胶质细胞脑源性神经营养因子及酪氨酸激酶受体B蛋白的表达

目的研究脑卒中后抑郁(PSD)大鼠海马小胶质细胞脑源性神经营养因子(BDNF)及其高亲和力受体酪氨酸蛋白激酶受体B(TrkB)蛋白的表达情况。方法将40只健康成年SD大鼠随机分为正常组、抑郁组、脑卒中组及PSD组,每组10只。用线栓法建立局灶性脑缺血模型;用慢性不可预见的中等应激刺激结合孤养法建立大鼠慢性应激抑郁模型。各组造模后第29和57天用免疫荧光双标染色法测大鼠海马OX42标记的小胶质细胞BDNF及TrkB表达情况。结果造模后第29天PSD组海马BDNF和TrkB阳性细胞吸光度(A)值分别为83.35±5.74和82.35±5.74,显著低于正常组、抑郁组和脑卒中组(P0.05);抑郁组A值较脑卒中组增多(141.23±9.16 vs133.31±7.89;141.23±8.07 vs 128.62±6.92,P0.05)。造模后第57天PSD组海马BDNF和TrkB阳性细胞A值分别为81.63±7.19,74.43±7.42,显著低于正常组、抑郁组和脑卒中组(P0.05);脑卒中组A值较正常组及抑郁组低(93.36±7.56 vs 124.11±11.39、116.65±10.55,87.14±6.56 vs 112.58±10.99、108.05±10.57,P0.05)。结论海马小胶质细胞在PSD发病过程中有重要意义,可能通过减少BDNF及TrkB的表达发挥作用。     

脑源性神经营养因子延缓动脉粥样硬化的机制

脑源性神经营养因子(BDNF)在神经系统的形成与发育中起重要作用,参与多种神经精神类疾病的发病。该文主要探讨BDNF在动脉粥样硬化发病过程中的作用机制。     

癫痫伴发抑郁大鼠额前皮质脑源性神经营养因子及其受体的表达研究

目的观察癫痫伴发抑郁(epilepsy-associated depression,EAD)大鼠额前皮质脑源性神经营养因子(brain-derived neurotrophic fctor,BDNF)及其高亲和力受体原肌球蛋白受体激酶B(tropomyosin receptor kinase B,Trk B)的表达情况。方法 52只雌性SD大鼠随机分为正常组、抑郁组(采用慢性不可预见中等应激刺激结合孤养法建立大鼠慢性应激抑郁模型)、癫痫组和EAD组,每组13只,后2组利用氯化锂-匹罗卡品建立癫痫模型,于造模后第14天对癫痫模型进行抑郁筛选,每只大鼠以抑郁各指标评分分别入癫痫组和EAD组。于造模成功后第4周分别用免疫荧光染色检测额前皮质BDNF及Trk B免疫阳性细胞表达;用Western blot检测额前皮质BDNF及Trk B蛋白定量表达。结果与癫痫组比较,EAD组额前皮质BDNF和Trk B阳性细胞数减少[(26. 08±1. 18)个/视野vs (32. 86±2. 28)个/视野,P 0. 05;(26. 48±4. 66)个/视野vs (35. 86±4. 37)个/视野,P 0. 05]。与正常组和癫痫组比较,EAD组额前皮质BDNF和Trk B蛋白表达明显减少(0. 522±0. 028 vs 0. 912±0. 035和1. 248±0. 066,P 0. 05;0. 494±0. 015 vs 0. 663±0. 024和1. 035±0. 048,P 0. 05)。结论 EAD大鼠额前皮质BDNF、Trk B蛋白的表达减少可能与EAD发病有关。     

局灶脑缺血大鼠脑源性神经营养因子及其受体的表达

目的：探讨脑缺血损伤与脑源性神经营养因子（BDNF）及其受体TrkB之间的关系。方法：用线栓法制备大鼠脑缺血模型，采用免疫组织化学方法及图像分析测定不同缺血时间额叶和顶叶BDNF及TrkB阳性神经元数目。结果：与假手术组相比，在额叶BDNF及TrkB阳性神经元数目于缺血开始增加（P＜0．05），缺血3d达到高峰（P＜0．001），缺血7d降至正常水平（P＞0．05）；在顶叶BDNF及TrkB阳性神经元数目于整个缺血过程均明显增加（P＜0．001）。结论：脑缺血损伤后，BDNF和TrkB表达同时增强，可能对脑缺血损伤有保护作用。     

脑源性神经营养因子在血管性痴呆发病中的作用

血管性痴呆是主要由脑血管病引起的获得性、持续性智能障碍综合征,是老年期痴呆的主要类型之一,其发病机制尚不明确。脑源性神经营养因子能够支持多种神经元的存活、发育、分化和损伤后修复,并通过调节海马突触传递和突触可塑性,诱发和维持海马和皮质长时程增强效应,改变海马神经元的形态可塑性等机制,参与海马依赖性学习和记忆过程,并可能在血管性痴呆的发病和发展中起重要作用。     

阿尔茨海默病中脑源性神经营养因子及其受体的变化

阿尔茨海默病是一种进行性中攀神经系统神经变性疾病,脑源性神经营养因子为一类在脑内广泛分布的神经营养因子类物质。由于它所具有的神经保护作用,和／或其体的含量变化可能与阿尔海默病的发病有关,研究发现,阿尔茨海默病患者脑内脑源性神经营养因子及其受体的水平确有降低;阿尔茨海默病动物模型中,脑源性神经营养因子可以在一定程度上缓解神经元变性。     

脑源性神经营养因子在肠道中的表达及其作用

脑源性神经营养因子(BDNF)既是一种神经营养物质又是一种神经递质,BDNF及其受体在肠神经系统、肠黏膜上皮和肠肌层中均大量表达,并在肠道感觉和肠道动力调节中起重要作用。本文就BDNF在肠道中的表达及其作用作一综述。     

脑源性神经营养因子与神经干细胞

脑源性神经营养因子在中枢神经系统的发育及脑损伤后神经干细胞的存活、增殖、分化和移行等方面具有重要的作用,这可能是其抗脑损伤的机制之一。     

脑缺血后适应通过上调脑源性神经营养因子和酪氨酸受体激酶 B减轻大鼠脑缺血再灌注损伤

目的：探讨脑源性神经营养因子（brain－derivedneurotrophicfactor,BDNF）和酪氨酸受体激酶B（tyrosine receptor kinase B, TrkB）在脑缺血后适应中的作用。方法 Wistar大鼠随机分为假手术组（9只）、缺血后适应组和缺血再灌注组,后2组根据再灌注时间进一步分为6、12、24、48和72 h亚组（各亚组各9只）。线栓法制作大脑中动脉脑缺血再灌注模型。应用氯化三苯基四氮唑染色法检测梗死体积（假手术组和各亚组各4只）,免疫组化染色法检测BDNF和TrkB蛋白表达水平（假手术组和各亚组各5只）。结果缺血后适应组各时间点梗死体积较缺血再灌注组显著缩小[6 h：（143．3±8．7）mm3对（166．8±7．5）mm3,t＝4．104,P＝0．006;12 h：（151．7±7．8）mm3对（171．6±9．1）mm3,t＝3．314, P＝0．016;24 h：（159．2±9．3）mm3对（177．1±7．6）mm3, t＝3．000, P＝0．024;48 h：（166．9±9．6）mm3对（184．9±9．0）mm3, t＝2．732, P＝0．034;72 h：（172．0±9．1）mm3对（198．1±8．2）mm3,t＝2．640,P＝0．039],且高倍视野下 BDNF[6 h：（23．98±4．07）个对（18．63±2．5）个,t＝2．479, P＝0．038;12 h：（27．64±3．18）个对（22．01±3．14）个, t＝2．817, P＝0．023;24 h：（34．82±4．17）个对（28．46±4．05）个,t＝2．446,P＝0．040;48 h：（34．30±3．27）个对（26．29±3．26）个,t＝3．872, P＝0．005;72 h：（28．77±3．53）个对（23．64±3．54）个,t＝2．297,P＝0．051]和 TrkB[6 h：（33．83±3．90）个对（21．51±3．86）个,t＝5．012,P＜0．001;12 h：（38．59±4．84）个对（23．41±3．67）个,t＝5．586, P＜0．001;24 h：（46．07±3．06）个对（28．78±3．61）个, t＝8．169, P＜0．001;48 h：（47．90±3．30）个对（29．51±3．81）个,t＝8．160,P＜0．001;72 h：（42．78±4．07）个对（27．46±3．19）个,t＝6．623,P＜0．001]阳性细胞数量均显著多于缺血再灌注组。结论缺血后适应能上调脑缺血再灌注后BDNF和TrkB蛋白表达水平,缩小梗死体积,BDNF／TrkB在缺血后适应中可能发挥着重要的神经保护作用。     

神经生长因子及其酪氨酸激酶A受体在慢性阻塞性肺疾病大鼠肺泡巨噬细胞中的表达

目的 观察神经生长因子(NGF)及其酪氨酸激酶A(TrkA)受体在COPD大鼠肺泡巨噬细胞的表达变化.方法 40只雄性SD大鼠,随机分为对照组和COPD组,每组20只.采用6个月单纯烟熏法建立COPD大鼠模型,并检测肺功能,HE染色观察肺组织病理变化.从支气管肺泡灌洗液中分离纯化出肺泡巨噬细胞,用酶联免疫吸附法测定肺泡巨噬细胞培养液的上清液中NGF蛋白表达,激光共聚焦法鉴定肺泡巨噬细胞以及半定量检测肺泡巨噬细胞的TrkA蛋白表达.实时荧光定量PCR法检测肺泡巨噬细胞的NGF mRNA及TrkA mRNA表达.两组间比较采用单因素方差分析,组间比较采用t检验.结果 COPD组大鼠肺顺应性为(0.15 ±0.03) ml/cm H2O(1 cm H2O =0.098kPa),每分通气量为(0.045±0.004)L,均显著低于对照组的(0.42±0.05) ml/cm H2O和(0.102±0.010)L,差异均有统计学意义(t值分别为9.46和12.99,均P＜0.01)；气道阻力为(0.038±0.004)cm H20·L-1·S-1,显著高于对照组的(0.016±0.002)cm H2O·L-1·s-1,差异有统计学意义(t=11.55,P＜0.01).肺组织病理显示,COPD组大鼠肺泡壁变薄,肺泡间隔破裂,肺泡腔不规则扩大,部分融合形成肺大疱,肺气肿形成.COPD组NGF蛋白表达量为(3.79±1.52) ng/L,显著高于对照组的(0.94±0.27) ng/L,差异有统计学意义(t=4.13,P ＜0.05).COPD组TrkA蛋白平均荧光强度值(19.5±1.5)显著高于对照组(11.2±1.9),差异有统计学意义(t=7.95,P＜0.05).COPD组NGF和TrkA的mRNA表达量(24.8±6.0和9.0±3.3)显著高于对照组(1.0±0.2和1.0±0.4),差异均有统计学意义(t值分别为8.48和5.16,均P＜0.05).结论 COPD组肺泡巨噬细胞高表达NGF及其TrkA受体,提示NGF及其TrkA受体可能介导肺泡巨噬细胞参与COPD的发病过程.     

地拉卓对THP-1由来巨噬细胞清道夫受体-B(CD36) mRNA表达的影响

目的 探讨地拉卓(dilazep,DZ)是否影响巨噬细胞清道夫受体(ScR)-B(CD36) mRNA表达过程.方法 利用人类单核细胞株(THP-1)由来巨噬细胞,通过Northern印迹方法观察DZ对巨噬细胞ScR-B(CD36) mRNA表达过程以及表达后的影响.结果 巨噬细胞ScR-B(CD36)mRNA表达随DZ浓度的增加而减弱;DZ对巨噬细胞ScR-B(CD36) mRNA表达后水平并无影响.结论 DZ的这种对巨噬细胞ScR-B(CD36) mRNA的表达过程具有抑制作用但对ScR-B(CD36) mRNA表达后水平并无影响的机制可能对动脉粥样硬化的形成早期具有保护作用而无治疗作用.     

Epidermal growth factor tyrosine kinase receptors and the neuroendocrine control of mammalian puberty

In recent years evidence has begun to accumulate indicating that the central control of mammalian puberty requires not only changes in transsynaptic communication, but also the participation of glial cells. Neurons and astrocytes control the pubertal process by regulating the secretory activity of those neurons that produce luteinizing hormone-releasing hormone (LHRH), the neuropeptide that governs sexual development. LHRH, in turn, directs sexual development by stimulating the secretion of pituitary gonadotropins. Astrocytes affect LHRH neuronal function via cell–cell signaling mechanisms involving several growth factors acting via receptors endowed with tyrosine kinase activity. We have identified two members of the epidermal growth factor/transforming growth factor alpha (EGF/TGF) family and their respective receptors as key players in the glial–neuronal interactive process that regulates LHRH secretion. Our results indicate that TGF and its distant congener neuregulin (NRG) are produced in hypothalamic astrocytes and stimulate LHRH release indirectly via activation of their respective receptors, located—surprisingly—not on LHRH neurons, but on astrocytes. Activation of EGF receptors by TGF, and/or the erbB2/erbB4 receptor complex by NRG, leads to glial release of prostaglandin (PG) E₂, which then acts directly on LHRH neurons to stimulate LHRH release. That a central blockade of TGF or NRG action delays puberty, and focal overexpression of TGF advances it, leads to the conclusion that both TGF and NRG are physiological components of the central mechanism controlling the initiation of female puberty.     

文拉法辛对老年抑郁大鼠海马血管内皮生长因子表达的影响

目的 探讨抗文拉法辛对老年抑郁大鼠海马血管内皮生长因子(VEGF)表达的影响.方法 老年雄性SD大鼠,随机分为3组,模型组、文拉法辛组各12只均给予慢性不可预测的温和多相应激结合孤养共5 w,文拉法辛组于应激第3周末开始同时给予文拉法辛(5 mg.kg-1.d-1)治疗持续14 d,模型组同时给予生理盐水14 d.对照组12只不给予任何处理.采用敞箱实验和糖水消耗实验观察大鼠抑郁建模情况.采用免疫印迹检测海马VEGF蛋白表达,逆转录聚合酶链反应(RT-PCR)检测VEGF mRNA表达.结果 敞箱实验、液体消耗实验显示模型组及文拉法辛组抑郁模型建立成功.与模型组比较,文拉法辛组垂直得分增高,蔗糖消耗增加(P均＜0.05).与对照组比较,文拉法辛组海马VEGF蛋白及VEGFmRNA表达均增加(P ＜0.05,P＜0.01);模型组海马VEGF蛋白及VEGF mRNA表达均下降(P＜0.05).文拉法辛组与模型组比较,文拉法辛组VEGF蛋白及VEGF mRNA表达均明显增加(P＜0.01).结论 文拉法辛可提高老年抑郁大鼠VEGF表达,并对血管新生可能起到促进作用.     

Elevation of acidic fibroblast growth factor mRNA in lesioned rat brain

A 40-base oligodeoxynucleotide probe is described which has been prepared corresponding to the amino acid sequence 9-22 of acidic fibroblast growth factor. Following electrophoretic separation of rat brain mRNA under denaturing conditions the probe hybridizes to a major polyadenylated mRNA species of approximately 4.8 kb. This mRNA is the same size as that reported for acidic fibroblast growth factor mRNA. The relative abundance of the hybridizing 4.8 kb mRNA species increases in rat brain 3 days after cortical lesion indicating increased expression of the gene for acidic fibroblast growth factor.     

Ontogeny of angiotensinogen mRNA and angiotensin II receptors in rat brain and liver.

The renin-angiotensin-system (RAS) is active in fetal and neonatal life. This study was undertaken to examine the ontogenic regulation of angiotensinogen (AT) gene expression and angiotensin II (A II) receptors in liver and brain. AT gene expression was studied in fetal, neonatal, adult and aged rats, using slot blot hybridization to quantify AT mRNA levels. During fetal life (gestational days 15-20), AT mRNA was more abundant in brain than in liver. Soon after birth, brain AT mRNA levels increased to a concentration 3 fold above fetal levels. In contrast, liver AT mRNA abundance increased 30-fold within 12 h of birth. Aging (3-20 months) resulted in a gradual decrease in AT mRNA in both the brain and liver. Liver A II receptors in the neonate were 2-fold higher than in the fetus, but returned to fetal levels by 8 weeks of age. In the brain, A II receptor abundance increased to a level 75% above fetal levels in 7 days old animals, but returned to fetal levels by 14 days of age. These studies suggest than in the fetus, the liver is not the primary source of AT but that unknown factors at parturition result in a dramatic increase in liver AT mRNA. In contrast, the more modest increases in brain AT mRNA parallel the gradual maturation of the CNS. In both tissues, further aging resulted in a gradual decrease in AT mRNA, reflecting either increased sensitivity to feedback downregulation by A II or age related increases in other extrahepatic sites of AT synthesis. Age related changes were also found in the A II receptor in both the liver and brain.     

爱普列特对大鼠前列腺凋亡相关基因及5α还原酶mRNA表达的影响

目的 评价爱普列特对对大鼠前列腺Bcl-2、Bax、CD34、eNOS及5α还原酶mRNA 表达的影响. 方法分别给予雄性大鼠爱普列特(爱普列特组)、非那雄胺(非那雄胺组)和生理盐水(正常对照组),观察大鼠Bcl-2、Bax、eNOs、微血管密度(MVD)以及2种5α还原酶mRNA的表达情况. 结果爱普列特组Bcl-2、eNOS、MVD(148±42、72.3±48.5、4.6±2.2)与非那雄胺组(152 ±59、144.8±80.8、4.9±1.3)及正常对照组(216±52、293.9±116.0、8.0±3.0)比较,3个指标均下降(F值分别为6.6、0、26.45、9.52、均P<0.01);Bax在爱普列特组为(390±167)、非那雄胺组为(311±155),较对照组(185±73)上升(F＝6.35,P＝0.004),三组Srd5_(α1)及Srd5_(α2)还原酶mRNA的表达差异无统计学意义(F值分别为0.427和0.58,均P>0.05). 结论爱普列特可以促进前列腺细胞凋亡,抑制血管牛成,减少微血管密度,但可能不能影响5a还原酶mRNA的表达,且其作用与非那雄胺相似.     

Brain-derived neurotrophic factor/tyrosine kinase B signaling regulates human trophoblast growth in an in vivo animal model of ectopic pregnancy

Although medical treatment of unruptured ectopic pregnancy using methotrexate has been established, development of more potent and safer medical treatment is needed due to limited indications and side effects of methotrexate. Brain-derived neurotrophic factor (BDNF) signals through its receptor tyrosine kinase B (TrkB) to regulate the growth of malignant trophoblastic, choriocarcinoma cell. We investigated possible involvement of this signaling system in nonmalignant human trophoblast growth in both ectopic and intrauterine pregnancy. Here, we demonstrated the expression of BDNF in syncytiotrophoblasts and extravillous trophoblasts (EVTs) together with TrkB in cytotrophoblasts and EVTs in human placental villi during both normal and ectopic pregnancies. Treatment of cultured villous explants with soluble TrkB ectodomain or a Trk receptor inhibitor K252a suppressed cytotrophoblast differentiation by inhibiting EVT outgrowth reflected by decreased levels of an EVT marker, human leukocyte antigen-G. These inhibitors also decreased cytotrophoblast proliferation and cellular viability based on histopathological analyses and monitoring glucose metabolism, together with increased apoptosis in cytotrophoblasts based on in situ terminal deoxynucleotidyl transferase-mediated 2'-deoxyuridine 5'-triphosphate nick end-labeling and caspase-3/7 assays. After xenotransplantation of human placental villi into SCID mice as an in vivo model of ectopic pregnancy, treatment with K252a suppressed transplanted villi growth as reflected by decreased cytotrophoblast differentiation and proliferation, reduced tissue levels of chorionic gonadotropin-β, and increased apoptosis and caspase-3/7 activities. Thus, paracrine signaling by the BDNF/TrkB system is important for human cytotrophoblast differentiation, proliferation, and survival, and inhibition of BDNF/TrkB signaling in cytotrophoblasts could provide a novel medical treatment for ectopic pregnancy.     

米诺环素对衰老痴呆大鼠脑组织eNOS、iNOS表达的影响

目的 观察米诺环素(minocycline)对衰老痴呆大鼠学习记忆和脑组织eNOS、iNOS表达的影响,探讨米诺环素对衰老痴呆脑保护作用机制.方法 Wistar大鼠随机分组:假手术组(S组)、痴呆模型组(M组)、米诺环素治疗组(MT组).酶联免疫吸附法和免疫组织化学法检测大鼠脑组织eNOS、iNOS的含量,行为学检测大鼠记忆学习改变.结果 MT、M组与S组大鼠前后两次跳台实验、水迷宫实验的结果有显著性差异(P＜0.01),MT组与M组大鼠前后两次跳台实验、水迷宫实验的检测结果有显著性差异(P＜0.01).MT组iNOS表达较M组降低(P＜0.01),MT组eNOS表达较M组增高(P＜0.01);MT组eNOS、iNOS表达较S组增高(P＜0.01);M组eNOS、iNOS表达较S组显著增高(P＜0.01).结论 米诺环素能降低衰老痴呆大鼠脑组织iNOS、增强eNOS表达抑制氧化应激反应发挥脑保护作用.     

Coexpression of N-methyl-D-aspartate and phencyclidine receptors in Xenopus oocytes injected with rat brain mRNA.

Recent evidence suggest that the N-methyl-D-aspartate (N-Me-D-Asp) channel is functionally and structurally associated with the phencyclidine (PCP) receptor, which mediates the psychotomimetic effects of PCP, sigma opioids, and dioxalanes. To investigate the relationship between N-Me-D-Asp and PCP receptors on a molecular level, we injected mRNA isolated from adult rat brain into Xenopus oocytes. In injected oocytes N-Me-D-Asp application (with glycine) evoked a partially desentizing inward current that was potentiated by glycine and blocked by D-(-)-amino-5-phosphonovaleric acid (D-APV), by Zn2+ and, in a voltage-dependent manner, by Mg2+. These results show that the distinguishing features of rat brain N-Me-D-Asp channels are reproduced in this translation system. In addition, kainic acid elicited a nondesensitizing inward current at short latency, and quisqualate elicited a delayed oscillatory inward current, presumably mediated by a second-messenger system. Responses to glutamate had both short-latency and delayed components. The PCP derivative N-[1-(2-thienyl)cyclohexyl]piperidine (TCP) blocked the N-Me-D-Asp-evoked current, and its potency was comparable to its binding affinity in rat brain membranes. Onset of block required the presence of antagonist. Antagonism was stereoselective in that the active ligand dexoxadrol was a more effective blocker than its relatively inactive stereoisomer levoxadrol. adrol. Other PCP receptor ligands, (+)SKF-10,047 and MK-801, also blocked. Potencies of compounds active at N-Me-D-Asp and PCP receptors in oocytes were comparable to those obtained previously in electrophysiological and binding assays on neural tissues. These results indicate the coexpression of neuronal PCP and N-Me-D-Asp receptors in Xenopus oocytes.