孤啡肽及其片段的合成、痛觉调节作用和对免疫功能的影响

目的：研究孤啡肽(NC)与其4个片段(NC(1-15)NH₂, NC(1-13)NH₂, NC(1-11)NH₂, NC(1-5)NH₂) 在痛觉调节和免疫活性上的变化,探讨NC的构效关系。方法：固相多肽合成法合成NC及其片段;甩尾法测定它们对小鼠的痛敏作用和对吗啡镇痛作用的拮抗;T细胞玫瑰花结形成百分率和红细胞免疫粘附能力评测对免疫功能的影响。结果：虽然NC及其片段均有痛敏作用并可拮抗吗啡的镇痛作用,但NC(1-11)NH₂和NC(1-5)NH₂比母体活性约降低100倍,而NC(1-13)NH₂和NC(1-15)NH₂与母体有相同的活性。NC及片段(0.3～3 nmol.kg^-1)对T细胞免疫功能均有促进作用;NC(1-11)NH₂(0.3 nmol.kg^-1)对红细胞的免疫粘附能力有促进作用;NC(1-5)NH₂(0.3～30 nmol.kg^-1)不影响红细胞的免疫功能。结论：C端在NC的构效关系中有重要的作用。     

速激肽受体拮抗剂对白三烯C4引起的豚鼠心血管反应的抑制作用

iv白三烯C₄(LTC₄)0.8nmol·kg^-1引起麻醉豚鼠血压降低和心脏微血管依文思蓝渗出增加。速激肽NK-1受体拮抗剂CP-96345 (2.06μmol·kg^-1,iv)和NK-2受体拮抗剂SR-48968(1.66μmol·kg^-1,iv)部分抑制心房微血管渗漏(分别为46.6%和37.5%);两药合用可明显抑制LTC₄引起的低血压和心房、心室微血管渗漏(分别为58.1%和54.1%),其作用与白三烯特异性拮抗剂ONO-1078(0.06μmol·kg^-1,iv)相似。结果表明速激肽NK-1和NK-2受体可能参与白三烯引起的低血压和心脏炎症反应。     

脑5-HT1A/1B、α2受体及腺苷酸环化酶参与了胍丁胺的抗抑郁作用

为了在单胺受体及受体后腺苷酸环化酶(adenylate cyclase,AC)水平探讨胍丁胺(agmatine,AGM)抗抑郁作用的精细机制,采用小鼠悬尾实验和强迫游泳实验观察AGM抗抑郁行为改变。采用放射免疫方法测定大鼠前额皮层突触膜蛋白AC活性。结果表明,AGM(5～40 mg·kg^-1,ig)在小鼠悬尾实验和强迫游泳实验模型上均有显著抗抑郁活性。同时伍用β受体/5-HT_1A/1B受体阻断剂吲哚洛尔(pindolol, PIN, 20 mg·kg^-1, ip)、 α₂肾上腺素受体拮抗剂育亨宾(yohimbine, YOH, 5～10 mg·kg^-1, ip)或咪唑克生(idazoxan, IDA, 4 mg·kg^-1, ip)对AGM(40 mg·kg^-1, ig)的抗抑郁活性具有显著拮抗效应; 而β受体阻断剂普萘洛尔(propranolol, PRO, 5～20 mg·kg^-1, ip)或5-HT₃受体拮抗剂曲匹西隆(tropisetron, TRO, 5～40 mg·kg^-1, ip)对AGM(40 mg·kg^-1, ig)的抗抑郁活性无显著影响。AGM(0.1～6.4 μmol·L^-1)与大鼠前额皮层提取的突触膜共孵可剂量依赖地激活AC活性, 而PIN(1 μmol·L^-1)或YOH(0.25～1 μmol·L^-1)均显著拮抗AGM(6.4 μmol·L^-1)对AC的激活作用; 慢性给予大鼠AGM(10 mg·kg^-1, ig, bid)或氟西汀(fluoxetine, FLU, 10 mg·kg^-1, ig, bid) 2 w也显著增强大鼠前额皮层基础及Gpp(NH)p 预激活的AC活性。本研究表明, 调节脑内5-HT_1A/1B和α₂等受体功能, 并激活前额皮层AC可能是AGM抗抑郁活性的重要机制之一。     

4－甲基－5－取代苯氧基－伯氨喹类似物的合成及抗疟活性的初步评价

以2-硝基-4-甲氧基-5-溴乙酰苯胺为原料，经6步反应，合成了7个4-甲基-5-取代苯氧基伯氨喹类似物(Ⅱ_2～8)。抗疟活性的初步评价结果表明，这类化合物对鼠疟 Plasmodium yoelii 的病因性预防作用明显优于伯氨喹．可达伯氨唪的4～8倍；同时，Ⅱ_2～8还有较强的杀血液裂殖体作用．Ⅱ_2,5,6,8在0.781 mg·kg^-1 的剂量对原虫的抑制率为100％。     

苯甲酰胺类衍生物的合成及扩血管活性

报道了22个苯甲酰胺类衍生物的合成,其中大多数化合物有不同程度的扩血管活性,化合物H_1,11,17,E_1,3对去甲肾上腺素[NE](10^-7mol·L^-1)引起的大鼠主动脉条收缩的抑制作用明显优于先导物N-(4-甲氧基苯甲酰基)-N′-肉桂基哌嗪,化合物H_7,15,E₇对85.7mmpL·L^-1KCl引起的大鼠主动脉条收缩有明显的抑制作用,进一步钾通道实验表明E1可能为ATP敏感型钾通道开放剂。并初步分析了此类化合物的构效关系。     

苯并吡喃-4-腙类化合物的合成及其血管舒张活性

目的寻找高效低毒并具有组织选择性的苯并吡喃类钾通道开放剂。方法以对氰基苯酚为原料,经酰化、Fries重排、环合、成腙和取代等反应合成了3个系列20个苯并吡喃-4-腙类新化合物,所有目标化合物结构均经IR,1HNMR,MS和元素分析确证,并测定其对低钾(30 mmol·L^-1 KCl)和高钾(80 mmol·L^-1 KCl)诱导的大鼠主动脉条收缩抑制作用。结果合成了20个新化合物(I_1～9,II_1～4和III_1～7)。离体扩血管活性实验表明,大部分化合物具有一定的血管舒张活性。结论化合物I₉,III₂和III₅对低钾诱导的血管收缩抑制活性在1×10^-6 mol·L^-1浓度下略低于对照药emakalim,但对高钾诱导的血管收缩抑制活性在浓度为1×10^-5 mol·L^-1下强于对照药emakalim,值得进一步研究。     

促性腺激素释放多肽(GRP)对体外培养小鼠垂体分泌LH的影响

合成的促性腺激素释放多肽(GRP)及其类似物GRp～NH₂,[Glu^7.9.14Lys^6.10]GRP(6～14),[phe¹⁴]GRP(5～14)和[phe¹⁴]GRP浓度在0.05mmol·L^-1时,具有刺激体外培养的小鼠垂体分泌LH的作用。其活性依此相当对照垂体的115.4,114.2,140,160和179%。小鼠于妊振第7～9天或第1～5天,每只sc[phe¹⁴]GRP1mg·d^-1,或于妊娠第2～4天每只sc[phe¹⁴]GRP(5～14)1mg·d^-1,有40～60%的妊娠动物出现死胎。     

消旋11-去甲胡桐素A的合成方法改进及其药理学评价

本文发展一个实用改进方法以合成具有抗人免疫缺陷病毒(HIV-1)的天然产物的类似物11-去甲胡桐素A［(±)-1］，方法改进包括以间苯三酚为起始原料与正丁酰乙酸乙酯在饱和氯化氢甲醇存在下，经过Pechmann反应生成5，7-双羟基-4-正丙基香豆素(3)，再与巴豆酸用多聚磷酸作溶剂及催化剂进行酰化，同时分子内环合得到收率为70%关键中间体苯并二氢吡喃酮(4)，并与缩醛1，1-二乙氧基-3-甲基-2-丁烯用微波辅助催化得到苯并吡喃(6)， 最后用Luche还原以CeCl₃·7H₂O作催化剂， 在低温下经NaBH₄选择性还原化合物(6)得到目标产物即消旋11-去甲胡桐素A (±)-1。上述4步反应总收率32%， 比原方法提高1倍。体外研究表明(±)-1对HIV-1(野株)及耐药株均有明显抑制逆转录酶和P24抗原的活性， (±)-1在细胞培养内分别与作用机制不同的3种治疗艾滋病药物(AZT、 T-20、 Indinavir)都有明显的协同作用。小鼠急性毒性， (±)-1的LD₅₀灌胃给药为735.65 mg·kg^-1， 腹腔给药为525.10 mg·kg^-1。小鼠灌胃给与(±)-1血浆峰浓度(C_max)与药时曲线面积AUC_0-∞分别为0.54 μg·mL^-1及1.08 (μg·mL^-1)·h。为了初步观察(±)-1的体内药效，采用血清药理学方法，小鼠腹腔注射1次(±)-1或临床有效对照药奈韦拉平，30 min和60 min后血清有相似的抑制HIV-1逆转录酶活性。实验结果提示去甲11-胡桐素A值得进一步研究。     

清热合剂体外抗腺病毒Ⅲ型作用

目的研究清热合剂对腺病毒Ⅲ型(adv₃)的抑制作用。方法采用细胞培养技术,以双黄连为阳性对照药,观察清热合剂在非洲绿猴肾细胞(VERO)和咽喉癌上皮细胞(HEP-2)中对adv₃的抑制作用。结果在VERO细胞中,清热合剂半数中毒浓度(TD₅₀)为31.62mg·mL^-1,抗adv₃的半数有效浓度(IC₅₀)为0.45mg·mL^-1,治疗指数(TI)为70.27;在HEP-2细胞中,TD₅₀为32.10mg·mL^-1,抗adv₃的IC₅₀为0.52mg·mL^-1,TI为61.73。清热合剂对adv₃抑制作用存在明显的量效关系(P<0.01)。结论清热合剂在VERO和HEP-2细胞中对adv有明显抑制作用。     

吡那地尔对低氧低糖诱导神经细胞凋亡的抑制作用

目的　探讨ATP敏感性钾通道(K_ATP)开放剂吡那地尔(Pin)对低氧低糖再复氧诱导的大鼠皮质神经细胞凋亡的影响。方法　用电镜和流式细胞分析技术,检测原代培养的大鼠皮质神经细胞凋亡。结果　低氧低糖再复氧可诱导大鼠皮质神经细胞凋亡。Pin (10^-5,10^-6,10^-7mol·L^-1 ) 3个剂量组均能降低凋亡细胞百分率,以10^-5mol·L^-1 组效果最好。上述作用可被K_ATP特异性阻断剂格列苯脲(Gli)所拮抗。结论　Pin对低氧低糖再复氧诱导的大鼠皮质神经细胞凋亡有明显的抑制作用,提示KATP通道在调控细胞凋亡的过程中可能起着重要的作用。     

NMR and quenched molecular dynamics studies of superpotent linear and cyclic α-melanotropins

Conformational searching, computer simulations, synthesis and NMR are used on a variety of α melanocyte-stimulating hormone (α-MSH) analogues to understand the physical characteristics required for biological potency. Peptides I (AC-[Nle⁴,Asp⁵,d -Phe⁷,Lys¹⁰]α-MSH(4-10)-NH₂), II (Ac-c[Nle⁴,Asp⁵,d -Phe⁷,Lys¹⁰]α-MSH(4-10)-NH₂) and III (Ac-[Nle⁴,Asp⁵,d -Phe⁷,Dap¹⁰]α-MSH(4-10)-NH₂ all show very similar conformational properties (backbone and side-chain torsional angles), and all display high biological potencies. The modeling results for these compounds are supported by the NMR data. Peptide IV (Ac-c[Nle⁴,Asp⁵,d -Phe⁷,Dap¹⁰]α-MSH(4-10)-NH₂) appears to have a markedly different conformation and has decreased biological potency.     

碳糊电极阳极伏安法测定秋水仙碱

在0.05mol·L^-1H₂SO₄介质中,用碳糊电极(石墨粉:液体石蜡油=1.5∶1)阳极扫描伏安法测定秋水仙碱,检测限1×10^-7mol·L^-1,检测线性范围4.0×10^-7～1×10^-3mol·L^-1,氧化时出现两个氧化峰,峰电位分别为1.07V和1.33VvsSCE,峰电位随pH值升高而正移。对原料和片剂进行了测定,均获得满意的结果。     

Synthetic glucagon antagonists and partial agonists

This paper reports the synthesis and the biological activities of six new glucagon analogues. In these compounds N-terminal modifications of the glucagon sequence were made, in most cases combined with changes in the C-terminal region which had been shown previously to enhance receptor affinity. The design of these analogues was based on [Lys^17.18,Glu²¹]glucagon,¹ a superagonist, which binds five times better than glucagon to the glucagon receptor, and on the potent glucagon antagonist [d -Phe⁴,Tyr⁵,Arg¹²]glucagon, which does not stimulate adenylate cyclase system even at very high concentrations. The N-terminal modifications involved substitution of His¹ by the unnatural conformationally constrained residue, 4,5,6,7-tetrahydro-1H-imidazo[c]pyridine-6-carboxylic acid (Tip) and by desaminohistidine (dHis). In addition we prepared two analogues (6 and 7), in which we deleted the Phe⁶ residue, which was suggested to be part of a hydrophobic patch and involved in receptor binding. The following compounds were synthesized: [Tip¹, Lys^17.18,Glu²¹]glucagon (2); [Tip¹,d -Phe⁴,Tyr⁵,Arg¹²,Lys^17.18,Glu²¹ glucagon (3); [dHis¹,d -Phe⁴,Tyr⁵,Arg¹², Lys^17.18,Glu²¹ glucagon (4); [dHis¹,Asp³,d -Phe⁴,Tyr⁵,Arg¹²,Lys^17.18,Glu²¹]glucagon (5); des-Phe⁶-[Tip¹,D-Phe⁴,Tyr⁵Arg¹²,Glu²¹ glucagon (6); des-Phe⁶-[Asp³,d -Phe⁴,Tyr⁵,Arg¹²,Glu²¹]glucagon (7) The binding potencies of these new analogues relative to glucagon (= 100) are 3.2 (2), 2.9 (3), 10.0 (4), 1.0 (5), 8.5 (6), and 1.7 (7). Analogue 2 is a partial agonist (maximum stimulation of adenylate cyclase (AC) approximately 15% and a potency 8.9% that of glucagon, while the remaining compounds 3-7 are antagonists unable to activate the AC system even at concentrations as high as 10^?5m . In addition, in competition experiments, analogues 3-7 caused a right-shift of the glucagon stimulated adenylate cyclase dose-response curve. Hence these compounds are glucagon receptor antagonists with respect to the glucagon receptor coupled to the adenylate cyclase system.     

高效液相色谱法测定4-[4″-(2″,2″,6″,6″-四甲基哌啶氮氧自由基)氨基]-4'-去甲表鬼臼毒素大鼠血浆浓度及药代动力学参数

建立了大鼠血浆中4-[4″-(2″,2″,6″,6″-四甲基哌啶氮氧自由基)氨基]-4'-去甲表鬼臼毒素(GP-7)浓度的HPLC测定方法。用ODS柱分离,甲醇-水-冰醋酸(59:41:0.6)为流动相,检测波长285nm。血浆甲乙醚-二氯甲烷混合液萃取,45℃水浴蒸干,残渣用流动相溶解进样,内标法定量;血药浓度在2～200μg·ml^-1范围内呈线性关系,r=0.9997,血浆最低检测浓度0.2μg·ml^-1,方法回收率94%～100%,日内、日间RSD2.29%～7.70%。大鼠ivGP-710,20,30mg·kg^-1,药代动力学过程符合二室开放模型,消除半衰期为39.8±10.8min。     

大环内酯类抗生素麦迪霉素的电化学特性

在K₂HPO₄,NH₄Cl+NH₃和NaOH的10%(v/v)乙醇水溶液中,除0.01mol·L^-1以上NaOH液作为支持电解质外,麦迪霉素的伏安波皆为两个峰。峰A相当于它的甲醛基还原波,峰B为催化吸附氢波。溶液pH对两峰有强烈的影响。实验表明伏安波有吸附特性,且不可逆。两峰的ip与麦迪霉素的浓度成正比,线性范围分别为3×10^-6～3×10^-5mol·L^-1和1×10^-7～4×10^-5mol·L^-1,检测限为:1×10-6mol·L^-1和5×10^-8mol·L^-1。可应用于麦迪霉素的定量测定。研究了两峰的特性和电极机理,测定了有关的物理常数。     

Structure–activity studies at the rat tachykinin NK2 receptor: effect of substitution at position 5 of neurokinin A

A series of analogues of neurokinin A(4–10) was synthesized using solid phase techniques with Chiron pins, and purified by HPLC. The potencies of 10 peptides with substitution at Ser⁵ were assessed at rat fundus NK2 receptors. In membrane binding studies with [¹²⁵I]-[Lys⁵,Tyr(I₂)⁷,MeLeu⁹,Nle¹⁰]-NKA(4–10), all compounds except [Asp⁵]NKA(4–10) showed reasonable affinity, and analogues with Lys and Arg substitutions were five-fold more potent than NKA(4–10). In functional studies, all peptides were able to contract the rat isolated fundus strips. Analogues with Phe, His and Asn substitutions were substantially weaker in functional than in binding studies, whereas there was an excellent correlation (r = 0.95) between binding and functional potency for the remaining seven peptides. [Phe⁵]NKA(4–10) is in fact neurokinin B(4–10) and this residue may be critical in determining selectivity between NK2 and NK3 receptors. Analogues with a basic residue (Lys, Arg) at position 5 showed both increased affinity and functional potency, whereas the neutral [Asn⁵]NKA(4–10) was equally as weak in contractile studies as the acidic [Asp⁵]NKA(4–10). However, [Glu⁵]NKA(4–10) and [Gln⁵]NKA(4–10) were no different from NKA(4–10). Our results could indicate the presence of a negative charge on the NK2 receptor, close to position 5 of NKA. This would facilitate interaction with positively charged side chains and impede interaction with negatively charged side chains, particularly the inflexible side chain of aspartic acid. Thus, not only the charge, but also the length of the side chain of the residue at position 5, seems to be important for interaction with the rat NK2 receptor.     

Plasma Protein Binding of the Experimental Antitumour Agent Acridine-4-carboxamide in Man,Dog, Rat and Rabbit

Abstract— The plasma binding of N-[2-(dimethylamino)ethyl]acridine-4-carboxamide (AC) was investigated in-vitro by equilibrium dialysis for 3 h at 37°C against isotonic phosphate buffer (pH 7·35) using [³H]AC. There were significant species differences with the smallest % free fraction (mean ± s.d.) occurring in human plasma (3·4 ± 0·2), followed by dog (8·1 ±0·4), mouse (14·8 ± 0·8), rat (16·3 ± 0·9) and rabbit (20·2 ± 0·7). In plasma from healthy individuals (n = 5), the % free fraction ranged from 2·7 to 3·8. In physiological solutions of human proteins, the greatest binding was observed for α-acid glycoprotein (AAG) (0·75 g L^?1) with a mean free fraction of 24·1 ± 2·2%, followed by albumin (40 g L^?1) with 31·6 ± 0·7 and 39·8 ± 2·5% for fatty-acid-free and globulin-free, respectively. There was also some binding to globulins (5 g L^?1) with a mean % free fraction of 70·3 ± 1·6 and 84·8 ± 2·2 for Conn's fraction I and IV, respectively. Binding data from the displacement of [³H]AC by increasing concentrations of AC in human AAG (0·75 g L^?1) or albumin solution (40 g L^?1) indicated that AAG had 10-fold greater binding affinity for AC (K_a, 7·8 × 10⁴ m^?1) compared with albumin (K_a, 6·8 × 10³ m^?1). In human plasma enriched with AAG there was a significant negative linear correlation (r = 0·932; P < 0·001) between % AC free fraction and increasing AAG concentration over the range 0·6–4·5 g L^?1. Small but significant (P < 0·05) increases in AC free fraction occurred in the presence of various metabolites (50 and 100 μm) but, of those tested, only N-monomethyl-acridine carboxamide increased the free fraction to the same extent as parent AC.     

白细胞介素类及白三烯类等炎性介质对肿瘤坏死因子α产生的影响

目的：研究白细胞介素类及白三烯类等炎性介质对小鼠腹腔巨噬细胞生成及分泌肿瘤坏死因子α(TNFα)的影响。方法：用L929作为靶细胞的结晶紫染色法测定巨噬细胞培养上清液及胞溶部分TNFα的含量。结果：重组鼠白细胞介素-1β(rmIL-1β)和重组人白细胞介素-8(rhIL-8)均能促进巨噬细胞产生TNFα,其中rhIL-8有很好的剂量相关性,对巨噬细胞胞溶部分的TNFα无影响;重组人白细胞介素-6(rhIL-6),白三烯B₄(LTB₄),白三烯C₄(LTC₄)及白三烯D₄(LTD₄)均不能促进巨噬细胞生成及分泌TNFα。结论：rhIL-8和rmIL-1β能促进小鼠腹腔巨噬细胞生成TNFα。rhIL-6, LTB₄, LTC₄和LTD₄对TNFα生成无影响。     

组胺H2受体激动剂和拮抗剂及抗癌药对正常人造血祖细胞和HL-60白血病细胞生长的作用

采用体外微量克隆培养体系研究了组胺H2受体激动剂4-甲基组胺(4-MH)和拮抗剂雷尼替叮(ranitidine)及抗癌药阿糖胞苷分别对正常人外周血粒-巨噬系祖细胞(PBCFU-GM)和HL-60白血病细胞生长的作用。当4-MH的浓度为10^-9～10^-6mol·L^-1时,可促进PBCFU-GM的增殖,4-MH的浓度增加至10^-4mol·L^-1时则表现为抑制PBCFU-GM的增殖。Ranitidine的浓度为10^-9～10^-5mol·L^-1时,表现出对PBCFU-GM增殖的抑制作用,但在10-6mol·L^-1剂量时对PBCFU-GM的抑制率低于50%,而在该剂量时对HL-60白血病细胞的抑制率已达100%,具有一定的选择性。抗癌药阿糖胞苷(Ara-C)对HL-60白血病细胞的抑制作用比对PBCFU-GM的抑制作用较强,但两者的IC₅₀值处于同一个数量级。在强化化疗剂量10^-5mol·L^-1时,Ara-C对HL-60白血病细胞和PBCFU-GM正常造血祖细胞的抑制率均达100%。