江浙蝮蛇毒纤溶酶的生化和药理性质特征

背景：蝰亚科、蝮亚科和眼镜蛇科等蛇毒中存在着一类能直接溶解纤维蛋白（原）的酶，称为纤维蛋白（原）溶酶（纤溶酶），可做为溶解在心肌梗死．中风等期间形成的血栓的抗栓药物。目的：分离纯化江浙蝮蛇毒纤溶酶，并分析其部分生物化学和药理性质。设计：对照观察实验。单位：广西医科大学蛇毒研究所。材料：实验于2003—07／2005-06在广西医科大学蛇毒研究所完成。昆明种小鼠，体质量18&;#177;25g，平均（20&;#177;2）g，鼠龄三四个月，由广西医科大学实验动物中心提供。蛇毒冻干粉由广西医科大学蛇毒研究所提供：方法：应用DEAE Sepharose CL-6B阴离子交换柱和HiPrep Sephacryl S100柱分离纯化纤溶酶，以高效液相色谱仪和聚丙烯酰胺凝胶电泳检测纯度、相对分子质量，应用等电聚焦电泳测定等电点，然后测定氩基酸组分及部分药理性质。主要观察指标：纤溶酶相对分子质量、等电点和氨基酸组成．抑制剂对纤溶酶的作用，出血活性实验，纤溶酶对家兔体内抗凝活性的作用。结果：纳入30只鼠和12只免全部进入结果分析．分离得到相对分子质量为59100，等电点为4．98，SDS—PAGE为一条带，高效液相色谱分析为单一峰的纤溶酶。该组分属于金属蛋白酶类。氨基酸组成分析表明它含较多的酸性氩基酸．有微弱的出血毒性。具有较强且持久的溶栓效果。结论：分离纯化得到了一种有微弱出血毒，具有较强抗凝活性的单一组分的酸性金属蛋白酶.     

肿瘤细胞热休克蛋白70多肽复合物的提纯

目的探讨从人肺腺癌传代细胞系GLC-82细胞提纯热休克蛋白70用以制备肿瘤特异性抗原。方法培养GLC-82细胞,43℃30 min热休克诱导HSP表达,低温高速离心、DEAE-52、Sephdex G-200层析法提纯HSP-70,十二烷基磺酸钠-聚丙烯酰胺凝胶电泳(SDS-PAGE)和ELISA法进行定量及定性检测。结果未经过热休克处理的GLC-82细胞提取HSP-70得率约为57μg/ml,适当的热休克处理后GLC-82细胞HSP-70得率约为75μg/ml。升高温度或延长时间均会导致细胞凋亡。结论热休克处理可以增加肿瘤细胞HSP-70的表达。     

江浙蝮蛇毒纤溶酶的生化和药理性质特征

背景:蝰亚科、蝮亚科和眼镜蛇科等蛇毒中存在着一类能直接溶解纤维蛋白(原)的酶,称为纤维蛋白(原)溶酶(纤溶酶),可做为溶解在心肌梗死、中风等期间形成的血栓的抗栓药物。目的:分离纯化江浙蝮蛇毒纤溶酶,并分析其部分生物化学和药理性质。设计:对照观察实验。单位:广西医科大学蛇毒研究所。材料:实验于2003-07/2005-06在广西医科大学蛇毒研究所完成。昆明种小鼠,体质量18～25g,平均(20±2)g,鼠龄三四个月,由广西医科大学实验动物中心提供。蛇毒冻干粉由广西医科大学蛇毒研究所提供。方法:应用DEAESepharoseCL-6B阴离子交换柱和HiPrepSephacrylS100柱分离纯化纤溶酶,以高效液相色谱仪和聚丙烯酰胺凝胶电泳检测纯度、相对分子质量,应用等电聚焦电泳测定等电点,然后测定氨基酸组分及部分药理性质。主要观察指标:纤溶酶相对分子质量、等电点和氨基酸组成,抑制剂对纤溶酶的作用,出血活性实验,纤溶酶对家兔体内抗凝活性的作用。结果:纳入30只鼠和12只兔全部进入结果分析。分离得到相对分子质量为59100,等电点为4.98,SDS-PAGE为一条带,高效液相色谱分析为单一峰的纤溶酶。该组分属于金属蛋白酶类。氨基酸组成分析表明它含较多的酸性氨基酸。有微弱的出血毒性。具有较强且持久的溶栓效果。结论:分离纯化得到了一种有微弱出血毒,具有较强抗凝活性的单一组分的酸性金属蛋白酶。     

人心脏型脂肪酸结合蛋白的纯化与鉴定

目的:以往的心脏型脂肪酸结合蛋白多来自牛、鼠等动物心肌组织,本实验构建了人左心室心肌组织纯化心脏型脂肪酸结合蛋白的新方法。方法:实验于2005-01/03在南京医科大学第一附属医院心血管病研究所完成。①实验材料:人心室肌由南京医科大学第一附属医院心血管病研究所提供。②实验过程:取20g人左心室肌在缓冲液中匀浆,多步骤离心后以(NH4)2SO4进行盐析→再次离心→沉淀缓冲液重悬透析得蛋白粗提液→Sephadex G-75凝胶过滤→电泳确定主要蛋白条带的收集管号合并收集→QSepharose Fast Flow阴离子交换层析→聚乙二醇浓缩→缓冲液透析得人心脏型脂肪酸结合蛋白。③实验评估:以SIGMA公司人心脏型脂肪酸结合蛋白为对照标准品;以Tricine-SDS-PAGE电泳鉴定相对分子质量;以鼠抗人脂肪酸结合蛋白单克隆抗体及羊抗鼠IgG对其进行Western印迹检测鉴定其特异性。结果:①Sephadex G-75凝胶过滤柱层析结果:各组分经Tricine-SDS-PAGE电泳检测证实,部分收集管中存在相对分子质量约14400的人心脏型脂肪酸结合蛋白。②阴离子交换柱层析结果:在洗脱液NaCl浓度达6mmol/L时,出现蛋白峰,人心脏型脂肪酸结合蛋白被洗脱;NaCl浓度达20mmol/L时,蛋白峰降至基线,蛋白洗脱结束。③纯化的人心脏型脂肪酸结合蛋白鉴定结果:经电泳显示其相对分子质量约为14000,纯度约为90%;Western印迹证实其可被抗人脂肪酸结合蛋白单克隆抗体特异识别,与对照标准品SIGMA公司人心脏型脂肪酸结合蛋白结果一致。实验从20g湿重心室肌中共纯化得到15.4mg心脏型脂肪酸结合蛋白,得率为0.77mg/g。结论:Sephadex G-75凝胶过滤柱层析及阴离子交换柱层析相结合,可用于人心脏型脂肪酸结合蛋白的纯化。     

人成釉蛋白C端肽的大量表达及纯化

目的:获得高纯度的重组人成釉蛋白C端肽。方法:实验于2001-01/2004-06在解放军第四军医大学口腔内科实验室解放军第四军医大学基础部生物化学与分子生物学实验室完成。①转化pRSET-A/成釉蛋白原核表达质粒入BL21(DE3)细菌进行大量培养,加入诱导剂IPTG至终浓度为0.1mmol/L,32℃继续振荡诱导培养5h,收集细菌,诱导菌体的裂解上清经金属螯合亲和层析,洗脱Ni-NTA结合蛋白,收集洗脱蛋白,聚丙烯酰胺凝胶电泳法鉴定。②离子交换层析缓冲液(pH 7.4,50 mmol/L Tris·Cl)平衡Q SapharoseHP层析柱,将初步纯化的蛋白样品加在Q Sapharose HP凝胶介质上,梯度洗脱结合的蛋白,收集洗脱峰,制样,聚丙烯酰胺凝胶电泳法鉴定洗脱蛋白。结果:①表达重组人成釉蛋白C端肽的金属螯合亲和层析结果:诱导菌体的裂解上清经金属螯合亲和层析,洗脱下Ni-NTA结合蛋白,经聚丙烯酰胺凝胶电泳法电泳证实获得初步纯化的重组人成釉蛋白C端肽,其中仍含一些杂蛋白。②重组人成釉蛋白C端肽的离子交换层析结果:获得多个蛋白洗脱峰,聚丙烯酰胺凝胶电泳法证实获得纯化的重组人成釉蛋白C端肽。结论:获得了纯化的人成釉蛋白重组蛋白。     

双氢青蒿素对肿瘤细胞及肿瘤动物模型的抑制作用

目的:观察双氢青蒿素对多种肿瘤细胞和动物移植瘤模型的抑制作用,分析其抗癌作用的特异性.方法:用MTT法、SRB法观察和比较双氢青蒿素对多种肿瘤细胞和正常人体细胞的抑制作用,采用小鼠的B16-BL6、H22和Lewis等肿瘤模型分析双氢青蒿素对肿瘤生长的抑制作用以及铁对双氢青蒿素抗肿瘤效应的药物协同作用.结果:双氢青蒿素对小鼠的B16-BL6、H22和Lewis肿瘤模型的肿瘤生长有较强的抑制作用;提前6 h口服少量硫酸亚铁,可明显增强双氢青蒿素对B16-BL6、H22的抗肿瘤效应;双氢青蒿素对K562、KB、HCT、SGC7901、Hela、HepG、BGC823、KCC853、Bel7402、A549、B16-BL6细胞均有抑制作用.IC50(μg/mL)分别为4.12、10.21、11.02、11.77、13.03、18.36、26.47、28.02、44.55、46.28、54.46.在17.5～35 μg/mL药物浓度作用下,正常细胞(HELF)有3%～5%生长,而肿瘤细胞没有增长,并有部分死亡.结论:双氢青蒿素对多种肿瘤细胞和动物移植瘤模型具有一定的选择性抑制作用,铁剂有抗癌协同作用.     

大豆分离蛋白对果蝇寿命的影响

背景：大豆蛋白具有降血脂、抑制肿瘤以及雌激素样作用等各种保健功效，但有关大豆分离蛋白对机体寿命影响的研究少见报道。目的：观察大豆分离蛋白对果蝇寿命的影响，以探讨其抗衰老与抗氧化作用机制。设计：以果蝇为研究对象的对照实验研究。单位：一所大学公共卫生学院营养与食品卫生教研室。材料：实验于2002-03／06在新疆医科大学公共卫生学院营养与食品卫生教研室果蝇室完成。美国野生型黑腹果蝇400只，雌、雄各半，由新疆医科大学公共卫生学院营养与食品卫生教研室提供。方法：将400只果蝇分为1个对照组(普通培养基)和3个剂量组(分别为基础培养基含0．2％，1．0％，5．0％大豆分离蛋白)。从实验第2天起，每天观察记录果蝇生存数和死亡数，直到全部果蝇死亡为止。计算果蝇平均寿命、半数死亡期和最高寿命。主要观察指标：果蝇平均寿命、半数死亡期和最高寿命。结果：与对照组相比，大豆分离蛋白明显延长了雌雄果蝇寿命，并呈剂量反应关系，以高剂量组作用明显，其中雌雄果蝇平均寿命分别延长24．5％和20．7％；半数死亡时间分别延长27．1％和22．0％；最高寿命分别延长13．9％和10．6％。结论：大豆分离蛋白能延长果蝇寿命，可能具有一定的延缓衰老作用。     

大豆分离蛋白对果蝇寿命的影响

背景大豆蛋白具有降血脂、抑制肿瘤以及雌激素样作用等各种保健功效,但有关大豆分离蛋白对机体寿命影响的研究少见报道.目的观察大豆分离蛋白对果蝇寿命的影响,以探讨其抗衰老与抗氧化作用机制.设计以果蝇为研究对象的对照实验研究.单位一所大学公共卫生学院营养与食品卫生教研室.材料实验于2002-03/06在新疆医科大学公共卫生学院营养与食品卫生教研室果蝇室完成.美国野生型黑腹果蝇400只,雌、雄各半,由新疆医科大学公共卫生学院营养与食品卫生教研室提供.方法将400只果蝇分为1个对照组(普通培养基)和3个剂量组(分别为基础培养基含0.2%,1.0%,5.0%大豆分离蛋白).从实验第2天起,每天观察记录果蝇生存数和死亡数,直到全部果蝇死亡为止.计算果蝇平均寿命、半数死亡期和最高寿命. 主要观察指标果蝇平均寿命、半数死亡期和最高寿命.结果与对照组相比,大豆分离蛋白明显延长了雌雄果蝇寿命,并呈剂量反应关系,以高剂量组作用明显,其中雌雄果蝇平均寿命分别延长24.5%和20.7%;半数死亡时间分别延长27.1%和22.0%;最高寿命分别延长13.9%和10.6%.结论大豆分离蛋白能延长果蝇寿命,可能具有一定的延缓衰老作用.     

穿膜肽-凋亡蛋白融合蛋白导入人脐静脉内皮细胞和人肺腺癌Anip973细胞的生物学特性

目的：在大肠杆菌内表达穿膜肽与凋亡蛋白的融合蛋白，观察其诱导肺腺癌Anip973细胞凋亡的活性，并了解其是否有剂量依赖性。 方法：实验于2005-08／2006-01在哈尔滨医科大学生物化学与分子生物学教研室完成。①在大肠杆菌中表达穿膜肽-凋亡蛋白并用IDA-Ni^2＋亲和层析纯化。②细胞增殖抑制实验：取对数生长期人脐静脉内皮细胞和Anip973细胞接种于96孔培养板中，培养12h后加入终浓度分别为0，10，20，30，40，50mg／L融合蛋白培养48h，弃上清，每孔中加入四甲基偶氮唑盐溶液（5g／L）20μL，继续孵育4h，检测吸光度，计算肿瘤生长抑制率。③取对数生长期人脐静脉内皮细胞、Anip973细胞，每种细胞分成两组：给药组加入终浓度为30mg／L穿膜肽-凋亡蛋白，对照组加入相同体积的磷酸盐缓冲液，继续培养48h。苏木精-伊红染色，光镜下观察细胞形态；溴乙啶／丫啶橙荧光染色观察细胞凋亡率。 结果：①细胞增殖抑制实验结果表明浓度为10～50mg／L穿膜肽-凋亡蛋白对人脐静脉内皮细胞没有明显抑制作用，对Anip973细胞呈剂量依赖性抑制作用，半数抑制浓度为27mg／L。②30mg／L穿膜肽-凋亡蛋白作用48h后，人脐静脉内皮细胞形态没有显著改变，对照组和给药组的凋亡率分别为（2．9&;#177;0．4）％和（3．1&;#177;0．6）％，没有显著差异（P〉0．05）；Anip973细胞可见到细胞皱缩，染色质浓缩和出现凋亡小体等凋亡特征性形态变化，给药组和对照组凋亡率分别为（36．8&;#177;1．7）％和（6．7&;#177;0．5）％，差异显著（P〈0．01）。 结论：穿膜肽-凋亡蛋白能诱导肿瘤细胞凋亡，这种作用呈剂量依赖性，而对正常细胞没有毒性作用。     

真菌抗原提取法制备马尔尼菲青霉菌纯蛋白衍生物

目的：探讨马尔尼菲青霉菌纯蛋白衍生物的提取方法。方法：采用液体表面膜培养方法培养马尔尼菲青霉菌,培养液经盐析和弱酸沉淀法纯化,再经透析和除菌,制成马尔尼菲青霉菌纯蛋白衍生物原液;应用Lowry法测定马尔尼菲青霉菌纯蛋白衍生物的蛋白含量,并利用小白鼠对其进行安全性检测。结果：马尔尼菲青霉菌纯蛋白衍生物的蛋白含量为40μg／ml,且具有良好的安全性。结论：马尔尼菲青霉菌纯蛋白衍生物的提取有望用于检查人体马尔尼菲青霉病的感染,及时对马尔尼菲青霉病进行诊断。     

Mechanism of action of the antitumour effect of K18

K18 is an anticancer drug for oral administration comprising about five molecules of melphalan, an alkylating drug, covalently bonded to human immunoglobulin G. This study measured the in vitro antitumour activity of K18, melphalan and immunoglobulin G on human myeloma cells (RPMI-8226) and the in vivo antitumour effects of K18 and melphalan in BALB/c nude mice bearing human lung cancer cells (LC-10). The relative tumour-inhibitory effect, in vitro, was found to be: immunoglobulin G less than K18 less than melphalan. This activity of K18 was about half the theoretical value indicating that melphalan molecules are not released easily from the conjugate. K18 showed strong antitumour activity in vivo which continued after stopping administration. On the other hand, the effects of melphalan did not continue after administration was stopped. The distribution of [125I] K18 and [14C]melphalan was examined in BALB/c nude mice 14 days after implantation of LC-10 cells. Radioactivity levels in the major organs showed a transient rapid increase followed by a gradual decline. In tumours, [14C]melphalan levels increased transiently and then decreased, whereas [125I]K18 levels persisted following intravenous administration.     

家蚕后部丝腺丝素蛋白的制备

背景:采用对天然蚕丝进行去丝胶蛋白而获得丝素蛋白的方法,无法完全去除具有显著免疫原性的丝胶蛋白.为此,为了得到完全不含丝胶的丝素蛋白,必须要选择其他方法.目的:对从家蚕后部丝腺直接提取丝素蛋白的方法进行初步评价,试图为相关研究提供实验依据.设计、时间及单位:重复测量试验,2008-07/2008-08西南大学生物技术学院,西南大学生命科学学院.材料:五龄家蚕(Bombyx mori)100头,由西南大学蚕丝,上物学实验室提供.方法:解剖五龄家蚕,取出后部丝腺,在双蒸水中溶解丝素蛋白,过滤,冷冻干燥,研磨,筛分(400目)备用.主要观察指标:对丝素蛋白粉末进行形态学观察,检测其粒径分布情况.计算丝素蛋白的得率.结果:通过本方法所提取的丝素蛋白呈乳白色颗粒状,粒径大小介于100～400 μm,平均每头五龄家蚕可制备出0.33 g丝素蛋白.结论:从家蚕后部丝腺直接提取丝素蛋白的方法简单易行,丝素蛋白得率较高,所制备的丝素蛋白纯度高,是理想的生物组织工程原材料.     

Immunotherapeutic and antitumour potential of thalidomide analogues

The immunomodulatory drug thalidomide has been shown to be clinically useful in a number of conditions including various immunological disorders and cancers. Clinical activity in vivo is attributed to the wide ranging immunological and non-immunological properties possessed by this drug; these include anti-TNF-α, T-cell co-stimulatory, anti-angiogenic activities and also direct antitumour activity. Recently, the design of compounds based on the thalidomide structure has led to the synthesis of analogues with greatly enhanced immunological activity and with similarly decreased toxicity. These derivatives fall into at least two categories; selective cytokine inhibitory drugs (SelCID), which are phosphodiesterase Type 4 (PDE4) inhibitors and immunomodulatory drugs (IMiD), similar to thalidomide which act via unknown mechanism(s). These compounds are in the process of being characterised in laboratory studies and are also now being assessed in Phase I and Phase I/II clinical studies. In this review we will highlight the properties of these two novel classes of compound in terms of their effects on both immunological and non-immunological systems in vitro. We will also describe how these studies are enabling the characterisation and development of these compounds into clinically relevant drugs in widely varying diseases. To this end we will describe the various clinical studies of lead compounds that are in progress and speculate as to the potential and future development of these exciting compounds.     

土鳖虫溶栓酶抗凝血及抗血栓作用的实验研究

目的探讨土鳖虫溶栓酶的抗凝血和抗血栓作用。方法给药后检测凝血时间、凝血酶原时间、血纤维蛋白原含量、血凝块溶解率。用体内、外血栓形成溶解实验检测抗血栓作用。结果土鳖虫溶栓酶0.25、0.5、1.0 mg/kg能明显延长小鼠凝血时间、大鼠凝血酶原时间,降低大鼠血纤维蛋白原含量,增加血凝块溶解率,延长大鼠颈动脉血栓形成的时间,缩短大鼠体外血栓长度,减轻血栓的湿重及干重。结论土鳖虫溶栓酶具有抗凝血和抗血栓作用。     

Intercellular trafficking and enhanced in vivo antitumour activity of a non-virally delivered P27-VP22 fusion protein

VP22, a structural protein from herpes simplex virus type I, exhibits the unique property of intercellular trafficking. This protein is exported from primary expressing cells and subsequently imported into neighbouring cells. This property is conserved when VP22 is genetically fused to a protein, making it a promising tool to enhance the delivery of a gene product. We chose to study the intercellular transport and biological effect of a fusion protein between the putative tumour suppressor gene p27(Kip1) and VP22. We show that in vitro, P27VP22 is able to spread as efficiently as VP22. Functionality of the P27VP22 protein was demonstrated by its ability to inhibit cyclin/CDK2 complexes activity. In proliferation and clonogenicity assays, transfection with the P27VP22 plasmid resulted in a stronger cell growth inhibition when compared to transfection with the p27(Kip1) vector. In vivo, sub cutaneous tumours established in nude mice were injected with naked DNA encoding P27 or P27VP22. Our results show that P27VP22 can spread in vivo and that injections of the P27VP22 plasmid resulted in a significantly greater antitumour activity than injections of the P27 plasmid. This study confirms the usefulness of VP22-mediated delivery and suggests that P27VP22 may have applications in cancer gene therapy.     

The alteration of protein profile of Walker 256 carinosarcoma cells during the apoptotic process induced by ultrasound

The objective of this study was to investigate the alteration of the protein profile in cells after sonication and to identify the key proteins involved in the process of cell apoptosis. Walker 256 carinosarcoma cells were exposed to focused ultrasound (US) at the intensity of 2.0, 7.0, 10.2, 14.2 and 17.0 W/cm2 (I(spta)) for 10 min in vitro and the morphologic and functional changes of the cells were detected by hematoxylin & eosin staining and flow cytometry, with double staining of fluorescein isothiocyanate (FITC)-labeled Annexin V/propidium iodide (PI). The protein compositions in the cells after sonication were detected by 2-D SDS polyacrylamide gel electrophoresis. Our results showed that apoptosis of Walker 256 carinosarcoma cells could be induced by US. The percentage of early apoptosis and secondary necrosis increased with increasing intensity of US irradiation. Comparing with the protein patterns of cells before sonication, it was found that around 420 new protein spots were present in the gel after sonication. Among them, Hsp60 and Bcl-2 like protein 13 were found to be involved in the process of cell apoptosis and US-induced apoptosis of the cells was probably performed through the pathway of promoting the activation of caspase-3.     

Comparison of Standing Balance Parameters Between Rolling Walker Users and Potential Rolling Walker Users: A Pilot Study

To identify differences in balance parameters between older actual rolling walker (RW) users and potential RW users, 26 mentally intact older individuals (13 RW users and 13 potential RW users) participated in this study. All potential users had received recommendations to obtain a RW in the preceding three months because of a history of falls or hospitalization during that time. The test was conducted with each subject performing a static stance without assistance on a force platform with eyes open. The results showed that the ellipse area, path length, and the range and velocity of body sway were significantly larger among the actual users than among the potential users (p <. 05). These suggest that the actual RW users had poorer postural control than the potential users under circumstance without a RW support.     

鼻疽诺卡菌NFA47650蛋白免疫保护作用评价

  目的  评估鼻疽诺卡菌NFA47650蛋白激活固有免疫信号通路的能力,并评价其免疫保护效果。  方法  利用生物信息学分析nfa47650序列特征,Blast比对其在鼻疽诺卡菌中的保守性;用纯化后的NFA47650蛋白刺激RAW264.7细胞,利用Western Blot免疫印迹检测MAPK信号通路激活水平、利用ELISA检测细胞上清中细胞因子诱导水平;将C57BL/6小鼠分成两组,分别免疫PBS及NFA47650蛋白3次,检测血清效价后感染鼻疽诺卡菌,并检测感染24 h后小鼠体温、体重变化、血清IgG水平、肺泡灌洗液中蛋白水平、LDH水平以及肺部菌载量、肺上清细胞因子等指标。  结果  NFA47650蛋白能够刺激RAW264.7细胞上调ERK、JNK、P38磷酸化水平,并诱导IL-10、IL-12、TNF-α、IFN-γ等多种细胞因子浓度升高。 另外,该蛋白免疫小鼠后可以产生高效价的抗血清,使肺部感染减轻,肺部菌载量减少。   结论  NFA47650蛋白作为一种免疫显性蛋白,能在鼻疽诺卡菌感染宿主过程中刺激机体产生抗体,诱导小鼠产生免疫应答,具有免疫保护作用。     

The effect of propranolol on protein synthesis and phagocytosis by polymorphonuclear leukocytes from newborn, children and elderly individuals

The effect of propranolol on protein synthesis by polymorphonuclear (PMN) leukocytes was assessed in subjects from four age categories: elderly individuals, grown-up children, small children and newborn babies. This function was inhibited in PMN cells from individuals of all age groups, but inversely proportional to the age of the individual, i.e. the younger the subject, the more inhibited was the protein synthesis by his PMN leukocytes. The phagocytic capacity of the PMN cells of elderly subjects was decreased in comparison with that of individuals from the younger age groups. Propranolol inhibited this cell function in cells from subjects of all categories, although the inhibition was more pronounced in the cells of the younger groups. The difference in the degree of inhibition of the cell function observed in the various age groups may indicate different functional properties of the cell membrane.