多巴胺抑制大鼠背角伤害性神经元初步观察

本实验用玻璃微电极细胞外记录方法,观察了脊髓局部应用DA对清醒大鼠背角伤害性神经元电活动的影响。发现DA对背角伤害性神经元的自发放电和RHS、TES诱发反应均有抑制作用;DA对TES诱发反应的抑制主要表现为后串放电脉冲数的减少,但在有些神经元还伴有后串放电的潜伏期延长、时程缩短或频率下降;DA的作用可被静脉注射DA能受体拮抗剂氟哌啶所翻转。本文在国内首次证实,DA对大鼠背角伤害性神经元具有抑制作用。     

Capillary electrophoresis with inhibited electrochemiluminescent detection for the trace analysis of epinephrine and dopamine

In this paper, a novel electrochemiluminescent (ECL) detection approach was developed for highly sensitive detection of ECL inhibitors based on the ECL inhibition of Ru(bpy)32+/2-(Dibutylamino)ethanol (DBAE) system. A microfluidic ECL detection cell was fabricated to couple with the capillary electrophoresis system, the electrochemical system and the postcolumn injection system. Both Ru(bpy)32+ and DBAE solutions were injected directly to the working electrode surface by a micro-infusion system to obtain a high and stable ECL signal. The performance of this setup was demonstrated by the analysis of two typical ECL inhibitors, dopamine and epinephrine. Under the optimal conditions, the limit of detection (LOD) for dopamine and epinephrine was 50nM and 5nM respectively. The proposed method was also successfully used for the trace analysis of dopamine and epinephrine in human serum samples.     

内生大麻素受体激动剂抑制异动症大鼠纹状体单胺类神经递质的释放

目的观察内生大麻素受体激动剂WIN 55,212-2对帕金森病左旋多巴相关异动症模型大鼠纹状体内单胺类神经递质释放的影响。方法采用脑内微透析和高效液相色谱在线递质测量法观察WIN 55,212-2腹腔内注射对异动症模型大鼠左旋多巴相关异动症状和纹状体内单胺类神经递质释放的影响。结果与溶剂注射相比,WIN 55,212-2注射显著抑制异动症模型大鼠左旋多巴皮下注射后的异动样症状(F1 263=44.071,P<0.001),同时明显减少纹状体内多巴胺的释放(F1 263=5.091,P<0.05)。结论纹状体内生大麻素受体可能通过抑制性的调节单胺类神经递质的释放来影响异动症模型大鼠的异动样症状。     

银杏叶提取物对帕金森病模型大鼠多巴胺神经元的保护作用

目的 探讨银杏叶提取物(EGb)对部分损毁的帕金森病(PD)模型大鼠多巴胺(DA)能神经元的保护作用及其可能机制.方法 65只健康雄性SD大鼠随机分为4组:对照组、PD组、银杏叶提取物(EGb)低剂量组(20 mg/kg)和高剂量组(40 mg/kg).采用免疫组化法观察大鼠黑质酪氨酸羟化酶(TH)阳性细胞数目的变化,...     

Electrocatalytic oxidation and determination of dopamine at a carbon ionic liquid electrode modified with nafion-L-aspartic acid composite film

The electrocatalytic oxidation of dopamine (DA) was studied by electrochemical approaches at a carbon ionic liquid electrode (CILE) modified with the composite film of nafion and L-aspartic acid (NL-CILE). The CILE was fabricated by replacing non-conductive organic binders with a room-temperature hydrophobic ionic liquid, 1-butyl-3-methyl-imidazolium hexafluorophosphate. The composite film of NL was used as matrix to adsorb DA and catalyze the oxidation of DA in phosphate buffer solution (PBS). The electrochemical response of DA was investigated at the NL-CILE, the traditional carbon paste electrode (TCPE), CILE and the nafion modified CILE (N-CILE) in 0.1M PBS (pH 7.4), respectively. The results showed the superiority of NL-CILE to N-CILE, CILE and TCPE in terms of provision of higher sensitivity, faster electron transfer and better reversibility. Under optimum condition, the oxidation peak current was rectilinear with DA concentration range from 0.1μM to 0.1mM, with a detection limit of 0.03μM (S/N=3) by differential pulse voltammetry. The proposed method was applied to determine DA in samples successfully.     

冲动与多巴胺系统在毒品依赖中的作用机制

毒品依赖是严重的社会和生物医学问题。虽然研究表明毒品依赖与中枢神经系统多巴胺及其受体密切相关,但是还未阐明多巴胺系统在毒品依赖中的具体作用机制。冲动性行为是不同成瘾物质依赖者的标志性特征,最近的研究提示,冲动在可卡因依赖形成中也扮演着重要角色,但尚未见报道在其他毒品依赖发生过程中的作用机制。因此需要改进现有的研究方法和思路,对冲动性行为与多巴胺系统的联合效应进行研究。这必将为毒品依赖遗传学的具体机制提供重要依据;为药理学开发最佳的治疗药物奠定基础;为毒品依赖治疗提供新的策略。     

运用单光子发射计算机断层扫描显像诊断帕金森病和血管性帕金森综合征

目的探讨99Tcm-TRODAT-1{99Tcm-2β-[N,N′-双(2-巯乙基)乙撑二胺基]甲基,3β-(4-氯苯基)托烷}脑显像在早期帕金森病(PD)和血管性帕金森综合征(VP)鉴别诊断中的意义。方法对确诊的47例早期PD患者、26例VP患者和30例年龄匹配的正常对照者分别进行99Tcm-TRODAT-1SPECT脑显像,应用计算机感兴趣区(regions ofinterest,ROI)技术分别计算各组双侧纹状体/小脑的放射性计数比值,并对结果进行比较分析。结果早期PD患者患肢对侧纹状体对99Tcm-TRODAT-1的摄取减少,患肢同侧和对侧纹状体/小脑的放射性计数比值均较正常对照者均值明显降低(P<0.05)。VP患者双侧纹状体区对99Tcm-TRODAT-1的摄取接近正常,患肢同侧和对侧纹状体/小脑的放射性计数比值与正常对照者双侧均值无显著差异(P>0.05)。结论99Tcm-TRODAT-1显像及半定量分析有助于PD的早期诊断及与VP的鉴别诊断。