人工栽培盐生肉苁蓉的苯乙醇苷类化学成分

目的研究人工栽培盐生肉苁蓉(寄主为囊果碱蓬)中的苯乙醇苷类化学成分。方法采用色谱技术分离纯化,根据理化性质和谱学数据鉴定其结构。结果从盐生肉苁蓉栽培品中分离得到7个苯乙醇苷类化合物,分别鉴定为松果菊苷(echinacoside,1)、肉苁蓉苷A(cistanosideA,2)、毛蕊花苷(acteoside,3)、异毛蕊花苷(isoacteoside,4)、2′乙酰基毛蕊花苷(2′acetylacteoside,5)、管花苷B(tubulosideB,6)、1O[2(4羟基苯基)乙基]6O(E)香豆酰基βD吡喃葡萄糖苷(EutigosideA,7)。结论首次对人工栽培盐生肉苁蓉的化学成分进行了研究,分离得到7个化合物,其中化合物7为首次从列当科植物中分得,化合物1-6为在该种植物栽培品中首次报道。     

转录因子NFATc在钙神经素介导的脑缺血再灌注损伤中的作用

目的研究转录因子NFATc及NF-κB在钙神经素介导的脑缺血再灌注损伤中的作用。方法Western blotting和EMSA分子生物学技术。结果与对照组相比较，CsA明显减低I/R组Fas配体和NFATc的蛋白表达;对照组、I/R组和CsA处理组I-κB-α蛋白表达无显著区别;未观察到对照组、I/R组和CsA处理组有phospho-I-κB-α蛋白表达;与对照组相比较，CsA明显减低I/R组Fas配体启动子远端和Fas配体启动子近端NFAT结合位点的NFAT-DNA结合活性(P<0.01)。结论转录因子NFATc参与钙神经素介导的脑缺血再灌注损伤，促进CD95配体分子的转录表达;NF-κB可能未参与钙神经素介导的脑缺血再灌注损伤的作用机制。     

吗啡对急性心肌缺血期大鼠丘脑束旁核神经元5-HT_(1A)受体mRNA表达的影响

目的:观察吗啡对急性心肌缺血期大鼠丘脑束旁核神经元5-HT1A受体mRNA表达的影响,探讨吗啡对急性心肌缺血伤害性刺激的作用及其机制。方法:将体重260g~280g的健康成年雄性SD大鼠18只,随机分为三组:对照组,即非冠状动脉扎闭组(C组),开胸后冠状动脉左前降支下穿线,不结扎;扎闭冠脉组(CAO组),扎闭冠脉6h;吗啡+CAO组(MCAO组),CAO前15min静脉注射吗啡1.25mg/kg,然后CAO6h。CAO6h处死动物,取含有大鼠丘脑束旁核的脑片行原位杂交。5-HT1A受体mRNA杂交结果检测采用IDA-2000数码显微图像分析系统进行半定量分析。结果:与C组比较,CAO组大鼠丘脑束旁核5-HT1A受体mRNA的表达增强(P<0.05),与CAO组比较,MCAO组5-HT1A受体mRNA表达降低(P<0.05)。结论:急性心肌缺血可诱发大鼠丘脑束旁核5-HT1A受体mRNA表达增强,5-HT1A受体参与急性心肌缺血伤害性刺激在丘脑束旁核的调制,吗啡可抑制急性心肌缺血诱发的大鼠丘脑束旁核5-HT1A受体mRNA的表达增强。     

Structure–activity relationships of arodyn,a novel acetylated kappa opioid receptor antagonist*,†

Abstract: We previously reported that the novel dynorphin A (Dyn A, Tyr‐Gly‐Gly‐Phe‐Leu‐Arg‐Arg‐Ile‐Arg‐Pro‐Lys‐Leu‐Lys‐Trp‐Asp‐Asn‐Gln) analog arodyn (Ac[Phe^1,2,3,Arg⁴,d ‐Ala⁸]Dyn A‐(1–11)NH₂, Bennett, M.A., Murray, T.F. & Aldrich, J.V. (2002) J. Med. Chem. vol. 45, pp. 5617–5619) is a κ opioid receptor‐selective peptide [K_i(κ) = 10 nm , K_i ratio (κ/μ/δ) = 1/174/583] which exhibits antagonist activity at κ opioid receptors. In this study, a series of arodyn analogs was prepared and evaluated to explore the structure–activity relationships (SAR) of this peptide; this included an alanine scan of the entire arodyn sequence, sequential isomeric d ‐amino acid substitution in the N‐terminal ‘message’ sequence, NMePhe substitution individually in positions 1–3, and modifications in position 1. The results for the Ala‐substituted derivatives indicated that Arg⁶ and Arg⁷ are the most important residues for arodyn's nanomolar binding affinity for κ opioid receptors. Ala substitution of the other basic residues (Arg⁴, Arg⁹ and Lys¹¹) resulted in lower decreases in affinity for κ opioid receptors (three‐ to fivefold compared with arodyn). Of particular interest, while [Ala¹⁰]arodyn exhibits similar κ opioid receptor binding as arodyn, it displays higher κ vs. μ opioid receptor selectivity [K_i ratio (κ/μ) = 1/350] than arodyn because of a twofold loss in affinity at μ opioid receptors. Surprisingly, the Tyr¹ analog exhibits a sevenfold decrease in κ opioid receptor affinity, indicating that arodyn displays significantly different SAR than Dyn A; [Tyr¹]arodyn also unexpectedly exhibits inverse agonist activity in the adenylyl cyclase assay using Chinese hamster ovary cells stably expressing κ opioid receptors. Substitution of NMePhe in position 1 gave [NMePhe¹]arodyn which exhibits high affinity [K_i(κ) = 4.56 nm ] and exceptional selectivity for κ opioid receptors [K_i ratio (κ/μ/δ) = 1/1100/>2170]. This peptide exhibits antagonistic activity in the adenylyl cyclase assay, reversing the agonism of 10 nm Dyn A‐(1–13)NH₂. Thus [NMePhe¹]arodyn is a highly κ opioid receptor‐selective antagonist that could be a useful pharmacological tool to study κ opioid receptor‐mediated activities.     

Monomeric and dimeric states exhibited by the kinesin‐related motor protein KIF1A

Abstract: KIF1A, a kinesin‐related motor protein that transports pre‐synaptic vesicles in neurons, was originally presumed to translocate along microtubules (MT) as a monomer. Protein structure predictions from its amino acid sequence failed to identify the long coiled‐coil domains typical of kinesins, which led researchers to believe it does not oligomerize into the canonical kinesin dimer. However, mounting evidence using recombinant chimeric protein indicates that KIF1A, like conventional kinesin, requires dimerization for fast, unidirectional processive movement along MTs. Because these studies are somewhat indirect, we wished to test the oligomerization state of native KIF1A, and to compare that to full‐length recombinant protein. We have performed hydrodynamic analyses to determine the molecular weights of the respective complexes. Our results indicate that most native KIF1A is soluble and indeed monomeric, but recombinant KIF1A is a dimer. MT‐binding studies also showed that native KIF1A did not bind to MTs in either the presence of AMP‐PNP, apyrase, or adenosine triphosphate (ATP), but recombinant KIF1A bound to MTs most stably in the presence of ATP, indicating very different motor functional states. To further characterize KIF1A's dimerization potential, we prepared peptides corresponding to the neck domains of MmKIF1A and CeUnc104, and by circular dichroism spectroscopy compared these peptides for their ability to form coiled‐coils. Interestingly, both MmKIF1A and CeUnc104 neck peptides formed homodimeric coiled‐coils, with the MmKIF1A neck coiled‐coil exhibiting the greater stability. Collectively, from our data and from previous studies, we predict that native KIF1A can exist as both an inactive monomer and an active homodimer formed in part through its neck coiled‐coil domain.     

寡糖Lewis A模拟肽对博莱霉素诱导的小鼠急性肺炎症性损伤的抑制作用

目的考察寡糖LewisA模拟肽对肺炎症性损伤的抑制作用。方法采用博莱霉素诱导小鼠肺产生炎症损伤 ,采用病理切片法观察LewisA模拟肽对炎症的影响。结果早期注射寡糖LewisA模拟肽可以抑制博莱霉素诱导的小鼠肺炎症性损伤。结论寡糖LewisA模拟肽可能作为抑制肺炎症性损伤的药物。     

环孢素A微乳口服液的制备及稳定性研究

目的以环孢素A为模型药物,研究微乳制剂在药剂学上的应用.方法根据微乳的拟三元相图,筛选微乳的处方,制备环孢素A微乳,以冷冻蚀刻电镜法和动态光散射法分别考察其形态和粒径,采用高效液相方法测定微乳中环孢素A浓度,考察含量及稳定性.结果环孢素A微乳制备简单,粒径分布均匀,是一稳定的制剂.结论微乳在药学上有广阔的应用前景.     

不同免疫分析仪在环孢素A血药浓度监测中的差异

目的:考察不同分析方法对环孢素A(CsA)血药浓度监测中的影响.方法:71例肝肾移植术后CsA样品分别用AxSYM和TDx测定.结果:TDx监测结果大于AxSYM监测结果.结论:AxSYM和TDx在环孢素A血药浓度监测中存在差异.     

羟基红花黄色素A在大鼠体内药物动力学的研究

采用HPLC法测定大鼠静注羟基红花黄色素A后的血药浓度.色谱柱为DiamonsilTM C18,甲醇-乙腈-0.45%磷酸溶液(32.5∶2.5∶65)为流动相,检测波长402nm.线性范围为0.1～200μg/ml,最低检测限为10ng/ml.日内、日间RSD小于7%.羟基红花黄色素A高、中、低浓度的回收率分别为90.8%、88.2%、82.2%;对2、6、18mg/kg剂量,AUC0→4h分别为5.34、13.50、35.25μg·h·ml-1,y(c)为0.1199、0.1290、0.1242 L/kg;Cl(s)为0.3743、0.4445、0.5107 ml/min.