光亲和标记测定烫伤大鼠肝胞液糖皮质激素受体分子量

本实验室以往的工作证明,大鼠烫伤后,不但有肝胞液糖皮质激素受体结合容量的改变,而且有表观解离常数的增大和糖皮质激素受体沉降系数的改变。本文采用[~3H]去炎松缩酮光亲和标记法测定了烫伤大鼠肝胞液糖皮质激素受体的分子量,和正常大鼠无显著差异,因而说明,受体沉降系数的改变不是由于受体结合亚单位分子量的改变所致。     

Regeneration of functionally active rat brain muscarinic receptor in vitro after inhibition with methylmercury chloride]

The effect of methylmercury on muscarinic receptors and the regeneration of functionally active muscarinic receptor in vitro by antagonists were investigated. The result showed that methylmercury chloride (MMC) inhibited the binding of [3H] QNB to muscarinic receptor of rat brain-lysed synaptosomes, with IC50 values of 4.18 mmol/L. Regeneration of functionally active rat brain muscarinic receptors after inhibition with methylmercury was achieved by 2,3-dimercapto-1-propanesulfonc acid, Na salt (DMPS) dithiothreitol (DTT), glutathione (GSH) and Cysteine. Blocking the sulfhydryl groups is suggested to be the molecular mechanism of inhibition of brain muscarinic receptors by methylmercury. Our results provide evidence that thiols chelate out mercuric cations that tightly bound to sulfhydryl groups in muscarinic receptor binding sites and regenerate [3H] QNB binding activity.     

THE RECEPTOR BINDING AFFINITIES, ANTIPROGESTERONE AND ANTIGLUCOCORTICOID ACTIVITIES OF MIFEPRISTONE AND LILOPRISTONE

With radioligand binding assays, the receptor binding affmities of mifepristone and lilopristone to the rabbit uterus cytosol progesterone receptor and the rat fiver cytosol glucocorticoid receptor have been measured. The relative binding affinities ( RBA ) of     

甲亢类阴虚及甲低类阳虚模型动物中枢胆碱能M一受体变化的实验研究

本文报告了利用放射性配基受体结合法分析测定了甲亢类阴虚和甲低类阳虚模型动物大脑中枢胆碱能M一受体的变化,以及养阴益气中药复方和温补肾阳中药复方对其影响,尝试从细胞生物学水平上对虚证的发病机理和中药复方治疗虚证的机制作些探讨。结果表明,甲亢类阴虚模型大鼠脑中枢胆碱能M一受体数量减少(P<0.05),素和力提高(P<0.05),养阴益气中药复方能提高其数量(P<0.05),降低其亲和力(P<0.05);相反,甲低类阳虚模型免大脑中枢胆碱能M一受体的数量增多(P<0.05),亲和力无明显改变,温补肾阳中药复方能降低其数量。提示中枢胆碱能M一受体的变化,可能是中医阴虚(甲亢)阳虚(甲低)病理生理功能改变的原因之一,中药对此具有纠正调整作用。     

糖皮质激素对兔脑、肺和肝组织糖皮质激素受体的调节

采用放射配基结合分析法，研究地塞米松（Ｄｅｘ）对兔脑、肺、肝的糖皮质激素受体（ＧＲ）的调节作用。结果发现，静脉注射Ｄｅｘ５ｍｇ／ｋｇ后兔肺、肝胞液ＧＲ的结合量明显下降，与对照组比较Ｐ＜０．００１，脑胞液ＧＲ与对照组比较无显著差异。提示糖皮质激素（ＧＣ）对兔不同靶器官ＧＲ的调节存在不同特点。     

人参茎叶皂苷对失血性休克大鼠糖皮质激素受体的影响

目的 观察人参茎叶皂昔(ginsenosides，GSS)对失血性休克大鼠糖皮质激素受体(GR)的影响，并分析其作用机制，为研制及时抢救失血性休克患者的天然药物制剂提供实验依据。方法 雄性SD大鼠随机分为失血性休克组和对照组，失血性休克组分别每日ig200，100，50mg／kg GSS水溶液，对照组和模型组ig蒸馏水2mL，共10d。以[^3H]地塞米松为配体，用一点分析法测脑和肝胞液GR结合活性(Rs)、半定量RT—PCR方法测肝胞液GR mRNA水平、放免法测血浆促肾上腺皮质激素(ACTH)和皮质酮(GC)浓度。结果 GSS组大鼠脑和肝胞液的GR结合活性高于单纯失血性休克组，其中以中剂量组最明显(P＜0．01)；GSS组大鼠肝胞液GR mRNA表达水平高于单纯失血性休克组；GSS组大鼠血浆ACTH和GC浓度和单纯失血性休克组没有明显差别。结论 GSS可减轻失血性休克大鼠GR结合活性的下降幅度，作用机制可能与其促进了GR mRNA表达有关，并可能存在一个最佳剂量。     

慢性给予糖皮质激素对大鼠肝胞液糖皮质激素受体的影响

给大鼠每天肌肉注射氢化可的松2mg/100mg体重,连续注射20天左右,引起了大鼠肝胞液[~3H]地塞米松特异结合部位的结合容量(R_0)明显减少,平衡解离常数(kd)增加。盐水对照组和处死前5小时和24小时一次注射氢化可的松对照组皆无明显变化。实验结果提示,慢性给予糖皮质激素对其受体具有反向调节的作用。     

发育期单眼形觉剥夺弱视模型猫视皮层谷氨酸受体状况的研究

目的 观察单眼形觉剥夺性弱视动物模型谷氨酸受体(GluRs)的变化,探索形觉剥夺性弱视发生的物质基础.方法 11只初生家养猫随机分为两组,处理组在3周龄时缝合单侧眼睑塑造单眼形觉剥夺性弱视模型,3月后用受体的放射性配体结合分析实验观测视皮层GluRs的结合位点数和亲和力.对照组未予特殊处理.结果 处理组视皮层GluRs结合位点数较对照组下降(P＜0.001),而KD值高于对照组(P＜0.001).两组放射性配体-受体结合实验的Hill系数均接近于1.L-[3,4-~3H]-谷氨酸与各型GluRs结合位点的亲和力相同,无正负协同效应.结论 单眼形觉剥夺性弱视动物模型视皮层GluRs亲和力低,GluRs参数出现异常,说明形觉剥夺性弱视的发生可能有一定的物质基础.     

米非司酮抗糖皮质激素活性的探讨

目的 :探讨米非司酮与糖皮质激素受体的相互作用关系及抗糖皮质激素作用。方法 :以3 H 地塞米松(3 H DEX)作为示踪物 ,采饱和竞争抑制分析法测定米非司酮与大鼠肝胞浆糖皮质激素受体的相对结合亲和力 ;以培养的大鼠胸腺细胞作为模型 ,采3 H 胸腺嘧啶脱氧核苷 (3 H TdR)掺入法 ,研究米非司酮糖皮质激素和抗糖皮质激素活性。结果 :米非司酮可与大鼠肝脏糖皮质激素受体结合 ,较低浓度范围内就可抑制地塞米松与糖皮质激素受体结合 ,与地塞米松相比较 ,米非司酮的相对结合亲和力 (RBA)为 (344 .4 1± 5 7.4 1,5 0 ) %抑制浓度 (IC50 )为 (4.2 1± 1.0 2 )nmol·L-1。在很低浓度时地塞米松就可明显抑制3 H TdR掺入培养的胸腺细胞DNA ,而米非司酮对3 H TdR掺入无明显影响 ,但在高浓度时对3 H TdR掺入有一定的抑制作用。同时米非司酮能拮抗地塞米松诱导的3 H TdR掺入抑制作用。结论 :米非司酮具有一定的糖皮质激素作用和抗糖皮质激素作用 ,但其糖皮质激素样作用比较弱。     

The hypotensive effect of BMY 7378 involves central 5-HT1A receptor stimulation in the adult but not in the young rat

BACKGROUND: Stimulation of central 5-hydroxytryptamine-1A (5-HT(1A)) receptors produces hypotension and bradycardia. We describe BMY 7378 (8-[2-[4-(2-methoxyphenyl)-1-piperazinyl]ethyl]-8-azaspiro[4.5]decane-7,9 dione) effects in cardiovascular function and [(3)H] 8-OH-DPAT (8-hydroxy-2-(di-n-propyl-amino) tetralin) binding sites in rat brain of different ages. METHODS: BMY 7378 was administered to anesthetized male Wistar rats (1, 3 and 6 months old) and blood pressure and heart rate were continuously recorded. Saturation of [(3)H] 8-OH-DPAT binding to 5-HT(1A) sites in brain membranes was determined. RESULTS: Basal diastolic blood pressure increased with age, 85 +/- 2, 106 +/- 3, and 113 +/- 2 mmHg for 1-, 3- and 6-month-old rats, respectively (p <0.05 among groups). BMY 7378 induced significant dose- and age-dependent hypotension. The selective 5-HT(1A) receptor antagonist, WAY 100635 (N-[2-[4-(2-methoxyphenyl)-1-piperazinyl]ethyl]N-(2-pyridinyl) cyclohexanecarboxamide), antagonized BMY 7378 effects in 6 month-old but not in younger rats. [(3)H] 8-OH-DPAT binding sites decreased in hippocampi and brainstem with maturation. CONCLUSIONS: Data suggest that BMY 7378 is a hypotensive agent in the rat, but that its actions are mediated, in part, by central 5-HT(1A) receptor stimulation in the adult and by a nonserotonergic mechanism in the young rat.     

孕期应激对痉挛幼鼠皮层NMDA受体含量的影响

目的探讨母体孕期应激与其子代痉挛症发生的相关性。方法痉挛模型的建立和放射性配基结合实验：受孕母鼠11只,随机分为两组,对照组5只,应激组6只。应激组进行慢性刺激（强迫母鼠在4℃冷水中游泳,1次/d,5min/次）直至分娩;对照组母鼠孕期不予刺激。仔鼠生后第12天腹腔注射N-甲基-D-天冬氨酸（N-Methyl-D-Aspartic acid,NMDA,7mg/kg）诱发痫样发作,通过[3H]MK-801结合NMDA受体,[3H]muscimol结合GABAA受体,从液闪仪中读数,计算受体含量,比较仔鼠皮层中NMDA受体含量。结果应激组仔鼠大脑皮层内兴奋性NMDA受体含量平均值为10 537fmol/L;正常组受体含量平均值为4 927fmol/L,差异有统计学意义（P=0.025）。结论母孕期应激与子代痉挛症发病具有相关性,能加大子代痉挛患病几率。     

Patterns of adrenoceptor change during liver regeneration of the Wistar Kyoto rat: a binding study.

BACKGROUND: Adrenoceptors have been involved in the regulation of hepatocyte proliferation after partial hepatectomy, as well as in primary culture. This report characterizes alpha 1- and beta-adrenoceptor change during the time-course of liver regeneration in adult Wistar Kyoto rats. METHODS: Saturation binding assays with [3H]prazosin or [3H]dihydroalprenolol (for alpha 1- and beta-adrenoceptors, respectively) were done in liver plasma membranes from 6-month-old rats subjected to 70% hepatectomy followed by hepatic regeneration. RESULTS: [3H]Prazosin and [3H]dihydroalprenolol binding gave control Bmax values of 101 +/- 10 and 12 +/- 1 fmol/mg protein and Kd of 0.50 +/- 0.10 and 4.1 +/- 0.4 nM for alpha 1- and beta-adrenoceptors, respectively. alpha 1-Adrenoceptor number and Kd increased at 24 and 48 h and returned to control values at 72 and 96 h after surgery, whereas beta-adrenoceptors augmented at 48 and 72 h, with a Kd change at 24 and 48 h posthepatectomy. CONCLUSIONS: These results suggest that dual control of alpha 1- and beta-adrenoceptor membrane expression could be involved in different steps during hepatocyte proliferation, and that Wistar Kyoto rats have a different adrenoceptor pattern expression from other rat strains.     

冬凌草甲素在体外对DNA、RNA和蛋白质合成的影响

采用[~3H]TdR、[~3H]UR和[~3H]leucine在体外参入ECA细胞的液体闪烁计数术,探讨冬凌草甲素对DNA、RNA和蛋白质合成的影响。结果表明:冬凌草甲素对DNA、RNA和蛋白质的合成均有明显抑制作用,其抑制程度的大小呈剂量相关性。它对DNA、RNA合成的抑制发生较早,恢复较快,对蛋白质合成的抑制作用较强且持久。终止药物作用后,[~3H]TdR参入曲线表明,该药对DNA合成的抑制属干扰代谢型。     

The purification of nucleoside diphosphate kinase from rat brain.

Nucleoside diphosphate kinase from the cytosol of rat brain was purified to electrophoretic homogeneity through a series of chromatography columns, including DE-52, AcA-34 Ultrogel, phenyl-Sepharose and Q-Sepharose. The molecular weight of the enzyme was 64,000 as estimated by gel filtration, and it consisted of 3 identical 19,000 subunits. [35S]-GTP gamma S binding and autophosphorylation of the enzyme, and inhibition of the GTPase activity of G-protein were used to screen for the enzyme. These methods were shown to be useful for purifying and assaying the enzyme.     

尼可地尔在抑制内皮素诱导的血管平滑肌细胞增殖中的作用

目的：探讨丝裂素活化的蛋白激酶（ＭＡＰＫ）,在ＡＴＰ敏感钾通道开放剂尼可地尔抑制内皮素（ＥＴ－１）诱导的培养大鼠血管平滑肌细胞增殖中的作用。方法：将１０~（－７）～１０~（－５）ｍｏｌ／Ｌ的尼可地尔导于培养血管平滑肌细胞,ＥＴ－１诱导培养大鼠血管平滑肌细胞增殖。用Ｗｅｓｔｅｒｎ Ｂｌｏｔ法测定磷酸化 ＭＡＰＫ蛋白表达。［~３ Ｈ］胸腺嘧啶核苷酸掺入测定平滑肌细胞 ＤＮＡ合成。结果：ＡＴＰ敏感钾通道开放剂尼可地尔抑制ＥＴ－１诱导的培养大鼠血管平滑肌细胞［~３Ｈ］胸腺嘧啶核苷酸掺入并同时剂量依赖性下调 ＭＡＰＫ蛋白表达。结论： ＡＴＰ敏感钾通道开放剂尼可地尔可通过下调ＭＡＰＫ的表达从而抑制ＥＴ－１诱导的培养大鼠血管平滑肌细胞增殖。     

细菌对苯噻唑力复霉素的耐药性与细菌膜屏障的关系

用EDTA处理对苯噻唑力复霉素耐药的大肠杆菌后,[~3H]-苯噻唑力复霉素掺入菌体的量增加,耐药菌对该药的敏感性提高,苯噻唑力复霉素抑制[~3H]-尿嘧啶核苷掺入菌体的作用增强。金色葡萄球菌和大肠杆菌的敏感菌株掺入[~3H]-苯噻唑力复霉素的量均明显高于耐药菌株。提示细菌对苯噻唑力复霉素的耐药性与细菌对该药的通透性下降有关。     

硫酸锌对5－HT与［~3H］granistron竞争NG108－15细胞中5－HT_3受体的影响

本文用放射配体结合测定法观察了硫酸锌对５－ＨＴ３受体激动剂５－ＨＴ与［３Ｈ］ｇｒａｎｉｓｅｔｒｏｎ竞争ＮＧ１０８－１５细胞中５－ＨＴ３受体能力的影响。结果证实，硫酸锌（１ｍＭ）能使５－ＨＴ竞争受体的浓度──反应曲线左移，半数抑制结合浓度降低（Ｐ＜０．０５），对斜率无明显影响。提示锌离子可能也影响５－ＨＴ３受体功能，有增强５－ＨＴ与５－ＨＴ３受体结合的作用。     

烫伤后大鼠肝糖皮质激素受体减少的机理——肾上腺部分切除动物的研究

部分去除肾上腺的大鼠烫伤后,血清糖皮质激素无明显升高,而肝胞液糖皮质激素受体(GR)却有升高的趋势,其中烫伤后6 h组和对照组的相差有非常显著的意义。进一步用打点杂交进行的研究表明,部分去腺大鼠烫伤后6h肝GR mRNA也有增加。这些结果提示,完整动物烫伤时肝胞液GR的减少依赖于血中糖皮质激素的升高。     

对氯苯丙氨酸对大鼠海马胞液皮质酮受体数量的影响

本实验以(~3H)皮质酮为配体,建立了去肾上腺大鼠海马胞液皮质酮受体的放射配体结合测定法,并对海马胞液皮质酮受体的结合特性以及对氯苯丙氨酸(pCPA)对皮质酮受体数量的影响进行了研究。测得的皮质酮受体具有可饱和性、有限的结合能力、高亲和力和高特异性的特征。Scatchard分析为一直线,表明测得的皮质酮受体是一个或一组kd值十分接近的受体。侧脑室注射pCPA 1mg4天后,海马5-HT含量明显降低,同时海马胞液皮质酮受体的最大结合客量(Bmax)显著升高,提示海马5-HT能神经元的功能性活动在控制海马胞液皮质酮受体数量的相对恒定中具有重要作用。