氯化甲基汞在体外抑制脑毒蕈碱受体结合的恢复效应

为研究甲基汞对脑毒蕈碱（Ｍ）受体的影响及常用拮抗剂对甲基汞引起该受体特异结合抑制的恢复效应，应用放射性配体结合技术进行了体外试验。结果显示，甲基汞能明显抑制３Ｈ－二苯基羟乙酸奎宁酯（３Ｈ－ＱＮＢ）与脑Ｍ受体的特异结合，ＩＣ５０为４．８ｍｍｏｌ／Ｌ。巯基化合物二巯基丙磺酸钠，二巯基苏糖醇，谷胱甘肽及半胱氨酸能使甲基汞抑制的３Ｈ－ＱＮＢ的结合不同程度地恢复，而乙二胺四乙酸、亚硒酸钠则无这种恢复效应，表明甲基汞对脑Ｍ受体的影响是汞与受体上巯基基团相互作用的结果，而含有巯基的拮抗剂能与受体上巯基团结合的甲基汞竞争结合，从而恢复脑Ｍ受体与配体的结合能力。     

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。     

咪达唑仑对健康成年大鼠和东莨菪碱大鼠脑内M受体的影响

目的:观察预先腹腔注射咪达唑仑对健康成年大鼠和东莨菪碱大鼠大脑皮层及海马组织中胆碱能毒蕈碱样受体(M-R)的近期和远期影响.方法:(1)近期影响组38只SD大鼠随机分为4组:对照组(Con,n=9),咪达唑仑组(Mid,n=9),东莨菪碱组(Sco,n=10),咪达唑仑+东莨菪碱组(Mid+sco,n=10).第1,2,3天,Mid组和Mid+sco组大鼠每天腹腔注射咪达唑仑50 mg/kg,Con组和Sco组大鼠每天腹腔注射同体积的生理盐水.第4,5,6天,Sco组和Mid+sco组大鼠每天腹腔注射东莨菪碱0.8 mg/kg,Con组和Mid组大鼠每天腹腔注射同体积的生理盐水.(2)远期影响组36只SD大鼠随机分为4组:对照组(Con,n=9),咪达唑仑组(Mid,n=9),东莨菪碱组(Sco,n=9),咪达唑仑+东莨菪碱组(Mid+sco,n=9).第1,2,3天,Mid组和Mid+sco组大鼠每天腹腔注射咪达唑仑50 mg/kg,Con组和Sco组大鼠每天腹腔注射同体积的生理盐水.第10,11,12天,Sco组和Mid+sco组大鼠每天腹腔注射东莨菪碱0.8 mg/kg,Con组和Mid组大鼠每天腹腔注射同体积的生理盐水.(3)给药完毕后急性处死大鼠,分离脑组织的皮层和海马,用放射配体结合分析法测定M-R与[3H]QNB的特异性结合量.选择近期影响组大鼠的海马组织进行M-R受体饱和实验,用Scatchard曲线分析受体的平衡解离常数(Kd)和最大结合容量(Bmax)的变化.结果:(1)近期影响组海马M-R与[3H]QNB特异性结合量Con组高于Mid组、Sco组和Mid+Sco组(均P＜0.01);Mid组高于Sco组(P＜0.05)和Mid+sco组(P＜0.01);Sco组高于Mid+sco组(P＜0.05).皮层M-R与[3H]QNB特异性结合量各组间比较,差异无统计学意义.Mid组、Sco组海马M-R Kd值高于Con组和Mid+sco组(P＜0.01);Con组Bmax值高于Mid组(P＜0.05)、Sco组和Mid+sco组(均P＜0.01),Mid组高于Sco组和Mid+sco组(均P＜0.01),Sco组高于Mid+sco组(P＜0.05).(2)远期影响组:Con组、Mid组海马M-R与[3H]QNB特异性结合量高于Sco组和Mid+sco组(均P＜0.01).各组间皮层M-R与[3H]QNB特异性结合量差异无统计学意义.结论:预先腹腔注射50 mg/kg咪达唑仑连续3 d对皮层M-R没有影响,可在短时期内降低健康成年大鼠和东莨菪碱大鼠海马M-R与[3H]QNB的特异性结合量与海马M-R密度和亲和力发生改变有关,对健康成年大鼠和东莨菪碱大鼠海马M-R与[3H]QNB的特异性结合量无长期影响.     

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.     

内毒素休克狗心脏胆碱能M-受体和肾上腺素能β-受体的变化

应用放射配体结合技术测定大肠杆菌内毒素休克狗休克各期心脏的M-受体和β-受体,发现休克代偿期心房M-受体明显增多,而心室β-受体无明显变化。     

实验性自身免疫性脑脊髓炎脑内咪唑啉受体密度变化初步观察

目的:探讨咪唑啉2受体(I2R)和实验性自身免疫性脑脊髓炎(EAE)发病的关系.方法:采用放射性受体-配体饱和实验,以[3H]idazoxan标记I2R,检测EAE大鼠脑内I2R受体密度和亲和力变化.结果:EAE大鼠脑组织的I2R受体密度上调74.5%(n=3,P＜0.05),I2R亲和力与对照组相比无统计学差异.结论:I2R在EAE大鼠脑组织中受体密度上调,可能与EAE发病有联系.     

Effects of Phenamiphos on Muscarinic Acetylcholine Receptor in the Brain Synaptosome in Rats and Its Mechanism

ＥｆｆｅｃｔｓｏｆＰｈｅｎａｍｉｐｈｏｓｏｎＭｕｓｃａｒｉｎｉｃＡｃｅｔｙｌｃｈｏｌｉｎｅＲｅｃｅｐｔｏｒｉｎｔｈｅＢｒａｉｎＳｙｎａｐｔｏｓｏｍｅｉｎＲａｔｓａｎｄ　Ｉｔｓ　ＭｅｃｈａｎｉｓｍＳＵＮＬｉ（孙黎），ＭＡＴａｎ－ｇｅｎｇ（马谭庚），ＬＩ...     

老年早期及老年晚期大鼠脑胆碱能M型受体的改变

采用放射自显影技术测定脑切片胆碱能Ｍ型受体，观察大鼠在老年早期和老年晚期不同脑区Ｍ型受体密度的变化。结果：所得脑切片自显影像灰度层次清晰，主要分布在皮质、海马、纹状体等部位，非特异结合灰度很低。图像分析仪分别给出不同脑区的平均灰度值，老年鼠皮质、海马、纹状体的灰度显著低于青年鼠，老年早期大鼠３个脑区分别降低２４８７％，１４１２％，１２７６％（Ｐ＜００５）；老年晚期分别降低２９４５％，２４３３％，１５３１％（Ｐ＜００５）。结论：老年大鼠大脑皮质、海马、纹状体部位胆碱能Ｍ型受体密度显著降低，老年晚期比老年早期降低的幅度更大     

大鼠局灶脑缺血—再灌注后M受体密度的变化

目的：研究大鼠局灶脑缺血－再灌注模型中Ｍ受体在不同部位随时间的变化。方法：采用线栓法阻断大鼠大脑中动脉,建立局灶性脑缺血－再灌注模型。以＾３Ｈ－ＱＮＢ作为放射性配基,在与动物模型脑片上的Ｍ受体结合后,将脑片标本有氚片上进行放射性自显影,测定自显影片上不同部位受体密度。结果：在缺血２ｈ组和再灌注２ｈ组,受体的密度没有改变。再灌注８ｈ组枕部皮层（ＯＣ）及颞部皮层（ＴＣ）部位Ｍ受体密度出现明显下降,但同再灌注２４ｈ组及再灌注７２ｈ组比,下降程度较轻。再灌注２４ｈ组及再灌注７２ｈ组的尾壳核（ＣＰ）、前脑皮层（ＦＣ）、ＴＣ、ＯＣ区域Ｍ受体密度也明显下降,两组间并无差异;同时,Ｍ受体减少区域显像明显。结论：Ｍ受体的数量并非在缺血及再灌注后即刻改变,而是经过一段时间后才逐步降低的。Ｍ受体显像可估计体内具有活性的胆碱能神经元密     

新合成的阿片受体配基对稳定转染μ阿片受体的CHO细胞的受体结合特性

目的：研究新合成的阿片受体配基对稳定表达于CHO细胞的μ阿片受体的结合特性。方法：采用细胞生物学和放射性配基结合的方法,以能稳定表达μ阿片受体的CHO细胞为模型,检测阿片受体配基[^3H]diprenorphine(^3H-dip)与μ阿片受体的饱和性结合特征及一系列新合成阿片配基的竞争性结合特征。结果：(^3H-dip)结合μ阿片受体的平衡解离常数Kd值为1.06nmol/L;受体最大容量Bmax为930fmol/mg蛋白。竞争性结合实验表明3^#和12^#配基对μ阿片受体的亲和力高于BAMGO和吗啡。2^#、6^#、8^#和9^#配基对μ受体的亲和力低于BAMGO和吗啡。结论：新配基3^#和12^#对μ亚型的阿片受体有良好的亲和力。2^#、6^#、8^#和9^#配基对μ受体的亲和力较低。     

EXPERIMENTAL WORK AND RESEARCH Study on Mechanism of Huanshao Dan (还少丹) in Brain Protection

ＩｎｔｒａｄｉｔｉｏｎａｌＣｈｉｎｅｓｅｍｅｄｉｃｉｎｅ（ＴＣＭ）,ＨｕａｎｓｈａｏＤａｎ（还少丹,ＨＳＤ）ｈａｓｂｅｅｎｃｌｉｎｉ ｃａｌｌｙｕｓｅｄｖｉａｏｒａｌａｄｍｉｎｉｓｔｒａｔｉｏｎｆｏｒｔｈｅｔｒｅａｔ ｍｅｎｔｏｆｃｈｒｏｎｉｃｎｅｕｒｏｄｅｇｅｎｅｒａｔｉｖｅｄｉｓｏｒｄｅｒｓｓｕｃｈａｓｄｅｍｅｎｔｉａａｎｄｏｔｈｅｒｓｙｎｄｒｏｍｅｓｗｉｔｈＹａｎｇＤｅｆｉｃｉｅｎｃｙｏｆＫｉｄｎｅｙ．Ｔｈｉｓｃｏｍｐｏｓｉｔｅｈｅｒｂａｌｆｏｒｍｕｌａｈａｓｐｒｏｖｅｄｔｏｒｅｔａｒｄａｇ…     

大鼠低位脑干M受体亚型分析

放射受体结合试验表明脑桥、延髓存在M_1受体(约30～40％)和M_2受体(约60～70％);皮层海马M_1受体为主(约90％),小脑为M_2受体。东莨菪碱对皮层海马M_1受体的亲和力是小脑M_2受体亲和力的22.72倍,阿托品对小脑M_2受体亲和力是对皮层海马M_1受体亲和力的3.89倍。结果提示东莨菪碱、阿托品分别对M_1、M_2受体有一定的选择性。     

用转染m2胆碱受体基因的CHO细胞观察知母皂甙元的作用

目的 观察知母甾体皂甙元(sarsasapogenin,SAR)对M2受体亚型的调节作用。 方法采用转染了m2胆碱受体基因的CHO细胞为模型,以非选择性的3H-QNB作单点放射配基结合分析。 结果CHO m2细胞受体密度在培养48h达顶峰,以后呈进行性下降。SAR对下降的CHO m2细胞M2受体密度有明显的上调作用,这一作用有一定浓度依赖性。结论SAR对下降的M2受体密度具有上调作用。     

Determination of the Molecular Weight of Photoaffinity Labeled Glucocorticoid Receptor in Scalded Rat Liver Cytosol

Previous work in our laboratory showed that,after scalding,there wasnot only a decrease of rat liver cytosol [~3H]-Dexamethasone specific binding sitesbut also an increase of apparent dissociation constant of [~3H]-Dex and change ofsedimentation coefficient of glucocorticoid receptor.The present study was carriedout using photoaffinity labeling of glucocorticoid receptor in rat liver cytosol.Itwas found that there was no significant difference between molecular weights ofglucocorticoid receptor of normal and scalded rats determined by SDS-polyacrylamide gel electrophoresis.Our result suggests that chnage ofsedimentation coefficient is not due to alteration of molecular weight ofglucocorticoid receptor binding subunit.     

Serotonin (5-HT1c) receptors in pig choroid plexus.

It is very important to find suitable reaction conditions to attain a high specific binding (specific/total binding) in the receptor binding study. Membrane homogenates of pig choroid plexus are known to have exclusively serotonin (5-hydroxytryptamine, 5-HT) receptor of the subtype 5-HT1c. In this study, we used the membrane preparation of pig choroid plexus tissue and the specific binding of [3H]5-HT was 72-84% to serotonin receptor subtype 5-HT1c, as defined by the inhibition of 1 uM 5-HT, when a radioligand concentration of 0.5 nM of [3H]5-HT was used in the assay. Analysis of the properties of specific [3H]5-HT binding in pig choroid plexus tissue membrane preparation revealed linear Scatchard plots. In Tris-HCl buffer without CaCl2, pargyline or ascorbic acid, high average of affinity dissociation constant (Kd) of 1.3 +/- 0.2 nM (SEM, n = 4) and also a high average of receptor density (Bmax) of 284 +/- 12 fmol/mg of protein were found. Pig choroid plexus proves to be a good material for 5-HT1c receptor binding study.     

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。     

Effects of propranolol on β- Adrenergic receptor of experimental acute myocardial infarction in rats

Summary By using receptor autoradiography to observe the distribution and density of receptors, the effects of propranolol, a β-blocker, on β-adrenergic receptor of experimental acute myocardial infarction (AMI) were studied. One week after ligation of proximate left anterior descend (LAD) coronary artery, [³H] DHA binding sites were markedly decreased in both infarctregion and non-infarct region. After treatment of propranolol (100 μg/kg), the [³H] DHA binding sites were obviously increased in the infarct region, and they were further decreased in the non-infarct region. The ratio of [³H] DHA binding sites of the infarct region to non-infarct region was from 0. 24 at LAD ligation to 0. 87 after propranolol treatment, which was close to 0. 97 of control group (sham operation). The results indicated that the propranolol acted directly on myocardial β- adrenergic through the receptor regulation of the balance of β-receptors between the infarct region and non-infarct region, and improvement of the myocardial consonation and contraction synergism, thereby protecting the heart affected by AMI.     

放射自显影技术研究老年大鼠不同脑区M胆碱受体的变化

目的： 观察自然衰老大鼠不同脑区Ｍ 胆碱受体包括Ｍ１ 亚型受体的变化。方法： 采用放射自显影技术显示大鼠脑Ｍ 受体,并用图像分析仪进行灰度分析,以反映Ｍ 受体在不同脑区的相对定量分布。结果： 所得脑切片自显影灰度层次清晰,主要分布在大脑皮质,海马,纹状体等部位,非特异结合灰度很低,图像分析仪分别给出不同脑区的平均灰度值,老年鼠皮质,海马,纹状体部位的灰度显著低于青年鼠,Ｍ 受体分别降低２４８７ ％ ,１４１２ ％ ,１２７６ ％ （ Ｐ＜ ００５） ,Ｍ１ 亚型受体分别降低１５７８ ％ ,８６９ ％ ,１２３６ ％ （ Ｐ＜ ００１） 。结论： 以上３ 个重要脑区Ｍ 胆碱受体密度的改变可能是脑衰老的一个重要机制     

哮喘大鼠孤束核内H3受体对呼吸道P物质样免疫反应物的影响

目的:探讨大鼠孤束核(NTS)内组胺H3受体对哮喘发作时呼吸道内神经源性炎症介质P物质(SP)含量的影响。方法:取健康雄性SD大鼠成功制备哮喘模型后诱发哮喘急性发作,采用中枢立体定位及核团微量注射技术,分组依次向NTS内微量注射无菌生理盐水、H3受体激动剂RMHA以及其拮抗剂Thio,利用肺内SP特异性抗血清、免疫组化法(SABC法)、葡萄糖氧化酶-DAB-镍染色和计算机图像分析等技术检测肺内SP的含量。结果:和对照组相比较,哮喘大鼠NTS内微量注射1μgRMHA,肺内SP样免疫反应物(SPR-IL)阳性数量显著减少、阳性密度降低,差异有显著统计学意义(P<0.01);如果在哮喘大鼠NTS内注射Thio5μg,则可拮抗RMHA的上述效应。结论:大鼠NTS内H3受体参与减少哮喘发作时神经源性炎症介质SP的释放,从而可能抑制哮喘发作。     

肺内M受体异质性的研究Ⅱ——豚鼠肺内两种不同亲和性M受体结合部位结合特性的初步研究

应用蛋白质修饰的方法,从分子水平对豚鼠肺内两种不同亲和性M受体结合部位的分子结合特性进行了研究。结果表明:这两种不同亲和性M受体结合部位在分子构象上存在着差异。在与配基结合时,高亲和性M受体结合部位依赖于受体蛋白质中巯基的存在,而低亲和性M受体结合部位则依赖于双硫键的存在。