孕酮对东莨菪碱所致记忆损伤小鼠的作用及机制

目的观察孕酮对东莨菪碱所致记忆损伤小鼠的作用及机制。方法东莨菪碱(1mg·kg-1,ip)造成小鼠记忆损伤模型,利用被动逃避实验评价小鼠记忆成绩,并测定给药后24h小鼠皮质和海马胆碱酯酶(AChE)和胆碱乙酰转移酶(ChAT)的活性。结果在被动逃避实验中,东莨菪碱造成小鼠记忆损伤,孕酮(1、10mg·kg-1,sc)预处理能减少跳台错误次数(P<0.05),延长跳台潜伏期(P<0.01)和避暗潜伏期(P<0.01)。东莨菪碱增加皮质和海马AChE活性,降低ChAT活性,孕酮(1mg·kg-1,sc)预处理抑制皮质和海马AChE活性的增加(P<0.01),升高皮质(P<0.05)和海马(P<0.01)ChAT活性。结论孕酮可以改善东莨菪碱所致记忆损伤,机制可能与其抑制皮质和海马AChE活性、升高ChAT活性有关。     

健脑丸对东莨菪碱致学习记忆障碍模型小鼠影响及其机制研究

目的：研究健脑丸对东莨菪碱致学习记忆障碍模型小鼠的影响及其机制。方法:设空白、模型、阳性及健脑丸高、中、低剂量组,连续给药30天后,注射东莨菪碱诱导记忆障碍;Morris水迷宫测定小鼠空间学习记忆功能;HE染色观察脑组织病理变化,检测海马匀浆组织中Ach、AchE和ChAT含量。结果：与模型组比较,各组潜伏期值均明显小于模型组（P<0.05）;健脑丸中剂量组目标象限路程百分比显著提高,ChAT、Ach水平显著提高,AchE显著降低（P<0.05）。与空白组比较,模型组神经元明显空泡化;与模型组比较,健脑丸能减少海马组织神经元空泡化。结论：健脑丸对东莨菪碱致学习记忆障碍模型小鼠空间学习及记忆能力具有改善作用,其机制可能与提高ChAT、Ach水平,降低AchE水平及保护海马神经元有关。     

长春西汀改善东莨菪碱诱导的小鼠学习记忆障碍及其机制的研究

目的：研究长春西汀对东莨菪碱诱导小鼠认知损害的影响及其作用机制。方法：采用腹腔注射东莨菪碱（0．8mg·kg^-1·d^-1）制备小鼠认知损害模型,长春西汀连续灌胃给药10d,每天1次,采用Morris水迷宫和避暗实验评价认知功能,并测定脑内乙酰胆碱（Acetylcholine,Ach）、乙酰胆碱酯酶（Acetylch01inesterase,AchE）水平。结果：长春西汀（3、6mg·kg^-1·d^-1）能显著缩短小鼠在隐藏平台实验中寻找平台的潜伏期,增加空间探索实验中平台所在象限停留时间百分率;减少避暗测试中的错误反应次数。长春西汀还能显著增加小鼠脑组织海马区和皮层区Ach含量,并降低AchE活性。结论：长春西汀可通过降低AchE活性,使小鼠脑内Ach含量增加,从而改善东莨菪碱所致的小鼠认知损害。     

氯肟衍生物对记忆障碍模型动物空间学习记忆障碍改善作用及其机制研究

目的研究氯肟衍生物arimoclomol和TCO-2对记忆障碍动物学习记忆能力的影响并初步探讨其机制。方法采用东莨菪碱致记忆获得性障碍小鼠模型和侧脑室注射Aβ1-42所致记忆障碍大鼠模型。动物分为正常组、模型组、多奈哌齐对照组、arimoclomol干预组和TCO-2干预组。正常组与模型组动物每日相同时间腹腔注射相应剂量的药物溶剂(生理盐水);多奈哌齐对照组及待测药物干预组分别给予相应剂量的药物。给药8 d后,采用Morris水迷宫方法检测动物的空间学习记忆能力,并且检测动物海马组织的乙酰胆碱酯酶活性;检测侧脑室注射Aβ1-42大鼠海马组织的Aβ1-42含量,并测定磷酸化tau蛋白表达。结果与模型对照组相比,给予两种氯肟衍生物的动物搜索平台潜伏期缩短,穿越平台次数增加,表明氯肟衍生物可以明显改善注射东莨菪碱或Aβ1-42引起的记忆障碍;给予氯肟化合物还能够明显降低脑内乙酰胆碱酯酶活性和Aβ1-42含量,下调磷酸化tau蛋白的表达。结论氯肟衍生物可改善东莨菪碱以及侧脑室注射Aβ1-42所致的记忆障碍,其作用机制可能与增强中枢胆碱能系统功能、降低脑内Aβ蛋白和磷酸化tau蛋白含量有关。     

天冰调督胶囊改善癫痫大鼠学习、记忆及对海马ChAT、AchE表达的影响

目的探讨天冰调督胶囊对癫痫认知学习记忆改变的影响.方法Sprague-Dawley大鼠腹腔注射印防己毒素(1.5 mg·kg-1·d-1)连续30d,制作反复发作癫痫模型,点燃模型随机分为模型组、天冰调督胶囊低、高(1.2,4.8 g·kg-1)剂量组、吡拉西坦组、丙戊酸钠和吡拉西坦组,各组均qd灌胃给药,连续给药28 d,以Morris水迷宫观察各组大鼠的空间学习记忆能力、免疫组织化学方法观察海马ChAT、AchE的表达变化.结果经过30 d点燃癫痫大鼠再观察治疗28 d,与正常组相比,模型组大鼠空间记忆能力明显降低(P＜0.01),海马CA1区胆碱乙酰转移酶(ChAT)免疫反应阳性数量显著减少,CA2区乙酰胆碱酯酶(AchE)免疫反应阳性数量增多(P＜0.05);天冰调督胶囊观察组学习记忆指标以及ChAT、AchE的表达,与模型组相比有不同程度改善(P＜0.05,P＜0.01).结论天冰调督胶囊可在一定程度上改善反复发作后癫痫大鼠的学习记忆能力.     

蜕皮甾酮对东莨菪碱致记忆障碍的改善作用

采用一次性被动迥避式反应方法(跳台法、避暗法)、水迷宫法及穿梭箱法研究了蜕皮甾酮对东莨菪碱造成的小鼠记忆障碍的改善作用.结果表明,蜕皮甾酮36、72mg/kg能明显改善东莨菪碱造成的记忆获得障碍,蜕皮甾酮18、36、72mg/kg能拮抗东莨菪碱引起的小鼠空间辨别障碍,蜕皮甾酮25、50mg/kg能改善东莨菪碱引起的大鼠主动迥避反应障碍,提示蜕皮甾酮能改善东莨菪碱造成的记忆损害.     

淫羊藿苷对淀粉样β蛋白片段25-35所致大鼠学习记忆障碍的改善作用

目的观察淫羊藿苷对淀粉样β蛋白片段25-35(Aβ25-35)所致阿尔茨海默病(AD)模型大鼠学习记忆能力的保护作用,并探讨其可能的作用机制。方法Wistar雄性大鼠,右侧海马内注射Aβ25-3510μg制备AD模型,次日起淫羊藿苷30,60和120mg.kg-1灌胃给药,连续14d,d15～19Morris水迷宫检测大鼠空间辨别学习记忆能力;d20检测海马组织中谷胱甘肽过氧化物酶(GSH-PX)、超氧化物歧化酶(SOD)及一氧化氮合酶(NOS)的活性,免疫组化法检测海马内乙酰胆碱酯酶(AChE)和胆碱乙酰转移酶(ChAT)的表达。结果与模型对照组比较,淫羊藿苷给药14d明显改善大鼠学习记忆能力;海马组织中SOD和GSH-PX活性升高,NOS活性降低;海马内AChE及ChAT的表达增加。结论淫羊藿苷可以改善Aβ25-35海马内注射所致AD模型大鼠的学习记忆能力,其作用可能与其增加AChE和ChAT表达,增强SOD和GSH-PX等自由基清除酶活性,降低NOS活性,减少NO释放等多种机制,促进胆碱能递质系统功能的恢复有关。     

人参皂苷Rg1脂质体对东莨菪碱诱导大鼠学习记忆障碍的改善及其作用机制

目的：观察人参皂苷Rg1脂质体（Rg1-L）对东莨菪碱诱导大鼠学习记忆障碍的改善，并探讨其相关机制，方法：制备东莨菪碱诱导大鼠学习记忆障碍模型。采用Y型迷宫评价Rg1-L对模型大鼠学习记忆的影响，并测定大鼠大脑皮质中乙酰胆碱酯酶活性。结果：Rg1-L可以显著改善模型大鼠学习记忆功能。同时抑制大脑皮质中乙酰胆碱酯酶活性。结论：Rg1-L对东莨菪碱诱导大鼠学习记忆障碍模型大鼠的学习记忆功能有显著的改善作用，其机制可能与抑制大脑皮质中乙酰胆碱酯酶活性、提高人参皂苷Rg1生物利用度有关。     

播娘蒿籽油对小鼠学习记忆能力的影响

目的探讨播娘蒿籽油对小鼠记忆获得障碍模型的影响。方法以跳台法和避暗法测试小鼠学习记忆的能力,用比色法测定小鼠脑组织胆碱乙酰转移酶(ChAT)、乙酰胆碱酯酶(AchE)活性,用碱性羟胺法测定乙酰胆碱(Ach)含量。结果播娘蒿籽油可减少小鼠跳台和避暗错误次数,并能增加小鼠脑组织乙酰胆碱(ACh)含量和胆碱乙酰转移酶(ChAT)活性,同时降低脑组织乙酰胆碱酯酶(AchE)活性,有助于小鼠空间学习记忆能力的改善。结论播娘蒿籽油可以显著促进小鼠记忆。     

孟鲁司特对东莨菪碱模型小鼠学习记忆及脑内胆碱能神经的影响

目的：研究孟鲁司特（Mon）对东莨菪碱（Scop）致痴呆模型小鼠学习记忆及脑内胆碱能神经的影响。方法：将动物按体重随机分为5组,正常对照组[溶媒（Veh）＋Veh]、阴性对照组（Scop＋Veh）、阳性对照组[Scop＋多奈哌齐（Done）2．0mg／kg]、低剂量孟鲁司特组（Scop＋Mon 1.0mg／kg）、高剂量孟鲁司特组（Scop＋Mon2．0mg／kg）。灌胃给药,除正常对照组腹腔注射生理盐水外,其他各组小鼠给药前30min腹腔注射东莨菪碱（1．0mg·kg^-1·d^-1）,连续给药14d后采用Morris水迷宫和Y迷宫实验测定学习记忆功能,并测定脑海马及皮层乙酰胆碱（ACh）水平及乙酰胆碱酯酶（TChE）的活性。结果：与阴性对照组相比,孟鲁司特（1．0、2．0mg·kg^-1·d^-1）能显著缩短Morris水迷宫隐藏平台训练的潜伏期,增加动物在空间探索实验中对目标象限的搜索时间及原平台所在位置的穿越次数,增加Y迷宫实验中正确反应次数。孟鲁司特还能显著降低小鼠海马及皮层乙酰胆碱酯酶活性,增加乙酰胆碱含量。结论：孟鲁司特通过抑制东莨菪碱所致的痴呆小鼠脑内乙酰胆碱酯酶活性增加乙酰胆碱含量,继而改善小鼠学习记忆损害。     

长苞凹舌兰提取物对亚急性衰老小鼠学习记忆和凋亡相关蛋白表达的影响

目的研究长苞凹舌兰提取物(CE)能否改善衰老小鼠的学习记忆能力,及其与神经元凋亡的关系。方法ipD-半乳糖120mg·kg-1·d-1和亚硝酸钠90mg·kg-1·d-1连续60d建立衰老模型,从d47开始igCE2.5,5,10mg·kg-1·d-1,连续14d。跳台实验检测小鼠的学习记忆能力;免疫组化染色测定海马内Bcl-2,半胱氨酸天冬氨酸蛋白酶-3(cas-pase-3)和Bax凋亡相关蛋白的阳性细胞数,并用图像分析系统进行灰度扫描。结果CE明显改善衰老小鼠的学习记忆能力,跳台实验的潜伏期明显延长,错误次数显著减少。衰老小鼠脑中Bcl-2阳性神经元减少,caspase-3和Bax阳性神经元增多。CE可抑制这些凋亡相关蛋白的阳性细胞数改变,从而可能阻断凋亡级联反应的发生。结论CE可增强衰老小鼠的学习记忆能力,其机制可能与抑制神经元凋亡有关。     

Effects of Coeloglossum. viride var. bracteatum extract on memory deficits and pathological changes in senescent mice

Previous studies have shown that injection of D-galactose could result in senescent performances in animals, that injection of NaNO2 could cause ischaemia and hypoxia in many organs, and combined injection of D-galactose and NaNO2 make normal mice taking on senescent performances in a shorter period. The aim of this study was to investigate the effects of CE, an extract from a Tibetan medicinal herb, Coeloglossum. viride (L.) Hartm. var. bracteatum (Willd.), on senescent mice. The step-down test was performed to evaluate the learning and memory function of mice. The activities of superoxide dismutase, adenosine triphosphatase, monoamine oxydase and the content of malondialdehyde were measured to determine the impairment of brain. The expressions of Bcl-2, Bax, and caspase-3 proteins in mouse hippocampus were studied by immunohistochemical staining. The data demonstrated that D-galactose and NaNO2 treated mice had significant deficits in learning and memory function. The reduced activities of superoxide dismutase, adenosine triphosphatase, increased activities of monoamine oxydase and level of malondialdehyde were also found. Bax and caspase-3 positive cells increased while Bcl-2 positive cells decreased remarkably. Treatment of CE (2.5, 5 mg.kg(-1)) ameliorated the memory impairment; rectified the biochemistry and neural system changes in mice. These results suggest that CE offers promise as a tool for treatment of senescence-related diseases.     

Protective effects of extract of Coeloglossum viride var. bracteatum on ischemia-induced neuronal death and cognitive impairment in rats

Our earlier study demonstrated that Coeloglossum viride (L.) Hartm. var. bracteatum (Willd.) extract (CE) significantly improved the impaired memory in mice caused by permanent two-vessel occlusion. To investigate whether chronic treatment with CE could influence cerebral ischemia-induced neuronal and cognitive impairments, we examined the effects of CE on two different kinds of cerebral injury: transient middle cerebral artery occlusion model of focal cerebral ischemia; four-vessel occlusion model of transient global forebrain ischemia. CE treatment (5 mg/kg, orally) significantly reduced lesion volume, and improved the performance of passive avoidance and rotarod motor tasks in transient middle cerebral artery occlusion rats. In the four-vessel occlusion model, neuronal cell loss in CA1 of hippocampus was significantly decreased and the performance in the Morris water maze was significantly improved in rats administered CE. We conclude that treatment with CE attenuated learning and memory deficits, motor functional disability, and neuronal cell loss induced by global or focal cerebral ischemia. These results suggest that CE may be a potential candidate for the treatment of vascular dementia.     

Effect of standardized extract of Marsilea minuta on learning and memory performance in rat amnesic models

Context: Marsilea minuta Linn (Marsileaceae) is a common Indian hydrophytic plant. Traditionally, the plant has been used as a sedative for the treatment of insomnia and other mental disorders. Background information of this plant has encouraged us to investigate its antiamnesic activity in rat.

Objective: Standardized ethanol extract of M. minuta was investigated for their putative role in learning and memory performance in normal and amnesic rats.

Materials and methods: Ethanol extract of M. minuta (EMM) was standardized for marsiline using HPLC. The effect of standardized extract of M. minuta (1.15% w/w marsiline) was tested in amnesic rat using elevated plus maze (EPM) and passive avoidance (PA) test. Amnesia was induced after scopolamine (1?mg/kg, s.c.) and electroconvulsive shock (150?mA, 0.2 s) treatment. Behavioral studies were further substantiated with acetylcholinesterase (AChE) activity and radioligand muscarinic receptor binding studies in rat brain regions.

Results: Oral administration of EMM at 200 and 400?mg/kg/day for 3 days significantly reversed the amnesia whereas, no per se effect was observed. In comparison to control, AChE activity in frontal cortex and hippocampus was found to be significantly (P <?0.05) inhibited by EMM. EMM at doses 200 and 400?mg/kg has significantly (P <?0.05) increased (+34 % and +40 % change in affinity, respectively) the binding of 3H-QNB in frontal cortex indicating the up regulation of the muscarinic receptors.

Discussion and conclusion: These findings suggest that standardized extract of M. minuta have excellent antiamnesic activity, probably mediating through central cholinergic system.     

三氯化铝对小鼠学习记忆和大鼠海马脑片长时程增强的影响

采用 icv1 % Al Cl3(每侧 2 μL,隔天注射 )的方法做成小鼠学习记忆障碍模型 ,观察了 Al Cl3对学习记忆行为的影响 ,并用微电极方法观察了不同浓度 Al Cl3(0 .0 1 - 1 0 0 μmol·L-1)对大鼠海马脑片长时程增强 (LTP)的影响 .结果显示 ,在跳台与避暗实验中 ,模型组小鼠错误次数明显增加 ,潜伏期明显缩短 ,但自发活动计数均无显著变化 .脑片实验中 ,Al Cl31 .0和 1 0 0 μmol·L-1浓度组明显抑制海马脑片产生 LTP.结果提示隔天大剂量 Al Cl3icv可降低学习记忆能力     

阿魏酸对血管性痴呆大鼠学习记忆障碍的改善作用及其机制研究

血管性痴呆(vascular dementia,VD)是一种严重威胁老年人生命健康的神经退行性疾病,随着人口的老龄化,VD发病率逐年上升,寻找安全有效的抗VD药物已成为药物研究的热点[1,2]。近年来,中医药以活血化瘀法治疗VD取得了较大进展[3?5]。川芎是一种典型的活血化瘀中药,始载于《神农本草经》,具有活血行气、祛风止痛的功效,广泛用于VD     

腺苷A1受体阻断剂对学习记忆的影响及机制分析腺苷A1受体阻断剂对学习记忆的影响及机制分析

目的探讨腺苷A₁受体阻断剂对学习记忆的影响及其与胆碱能、氨基酸能神经的关系。方法采用避暗实验、分光光度法和HPLC法,观察腺苷A₁受体特异性阻断剂8-环戊-1,3-二丙基黄嘌呤(DPCPX)对东莨菪碱(Scop)、2-氨基-5-磷戊酸(AP₅)致小鼠记忆障碍及脑胆碱酯酶(AChE)活性、氨基酸水平的影响。结果DPCPX可显著改善Scop致记忆障碍,但对AP₅致记忆障碍无影响；在体内外高剂量DPCPX可显著抑制小鼠脑AChE活性；DPCPX icv可显著升高小鼠脑Glu和Asp含量,降低GABA含量,使脑内Glu/GABA比值显著升高。结论腺苷A₁受体特异性阻断剂DPCPX可显著改善Scop而不能改善AP₅致记忆障碍,在高剂量时可影响脑AChE活性和脑氨基酸水平、升高脑内Glu/GABA比值。     

红景天水提物和辅酶Q_(10)合用对小鼠学习记忆的协同促进作用

目的研究红景天水提物和辅酶Q10对Alzheimer病模型的协同保护作用。方法通过乙酰胆碱酯酶体外试验、NaCN及缺糖引起的PC12神经细胞损伤模型、东莨菪碱所致记忆障碍模型小鼠试验,并采用水迷宫评价促智作用,以小鼠皮层内乙酰胆碱酯酶活性,血清中单胺氧化酶、超氧化物歧化酶及丙二醛的活性水平为指标,检测红景天水提物和辅酶Q10的促智作用。结果红景天水提物和辅酶Q10对乙酰胆碱酯酶具有协同抑制作用,对神经细胞损伤具有协同保护作用,对东莨菪碱所致小鼠的空间辨别学习记忆障碍具有明显协同改善作用。结论红景天水提物和辅酶Q10对动物学习记忆有明显协同促进作用,其作用机制可能与红景天水提物能抑制胆碱酯酶活性而辅酶Q10有抗氧化作用有关。     

The ameliorating effect of the extract of the flower of Prunella vulgaris var.lilacina on drug-induced memory impairments in mice

Prunella vulgaris var. lilacina is widely distributed in Korea, Japan, China, and Europe, and its flowers are used to treat inflammation in traditional Chinese medicine. In the present study, we studied the effects of the ethanolic extract of the flower of P. vulgaris var. lilacina (EEPV) on drug-induced learning and memory impairment using the passive avoidance, the Y-maze, and the Morris water maze tasks in mice. EEPV (25 or 50 mg/kg, p.o.) significantly ameliorated scopolamine-induced cognitive impairments in the passive avoidance and Y-maze tasks (P < 0.05). In the Morris water maze task, EEPV (25 mg/kg, p.o.) significantly shortened escape latencies in training-trials. Furthermore, swimming times within the target zone during the probe-trial were significantly increased as compared with scopolamine-treated mice (P < 0.05). In addition, the reduced latency induced by MK-801 treatment in the passive avoidance task was ameliorated by EEPV (25 mg/kg, p.o.) (P < 0.05). Additionally, the ameliorating effect of EEPV on scopolamine-induced memory dysfunction was antagonized by a sub-effective dose of MK-801. These results suggest that EEPV would be useful for treating cognitive impairments induced by cholinergic dysfunction, and that it exerts its effects via NMDA receptor signaling.