睾酮对大鼠再生肝细胞转录活性的影响

以血清睾酮(testosterone,T)和核仁组织区相关嗜银蛋白(argyrophil nucleolar organiting regions,AgNORs)为指标,探讨去睾丸大鼠部分肝切除(partial hepatectomy,PH)后,外源注射睾酮对其血清睾酮水平及再生肝细胞DNA转录活性的影响.结果显示:外源睾酮可使大鼠血清睾酮水平显著升高,呈明显剂量-时间效应.除低剂量睾酮(0.5mg/kg体重)处理外,其它各组再生肝细胞AgNORs颗粒数在PH后24h均明显下降,PH后24～72h又持续升高.PH后各时期,低剂量睾酮使AgNORs数目显著高于芝麻油组;而中、高剂量睾酮(2.5mg/kg和5mg/kg体重)使AgNORs数目减少,并呈现明显剂量-效应关系.结果表明:低剂量睾酮对肝细胞的转录活性起促进作用;中、高剂量则起抑制作用,且随着睾酮浓度升高,抑制作用增强.     

黄芪不同溶剂提取物抑制前列腺增生的研究

通过比较黄芪不同溶剂提取物对前列腺增生的抑制作用,为寻找黄芪抗前列腺增生作用的活性成分奠定基础。比较了3种不同浓度乙醇提取物及水提取物对前列腺增生模型大鼠前列腺系数大小、离体膀胱逼尿肌的收缩强度、血清睾酮和二氢睾酮浓度的影响。结果表明,黄芪4种溶剂提取物组对模型大鼠的前列腺系数均具有较好的抑制作用（P<0.01）,95%乙醇提取物作用更明显,与其他3组相比具有显著差异（P＜0.05）;4种提取物还能增加模型大鼠膀胱逼尿肌条收缩强度,降低模型大鼠血清睾酮和二氢睾酮的浓度,其中95%乙醇提取物组作用更强,与其他提取物组比较有显著的差异（P<0.01）。黄芪不同溶剂提取物对大鼠前列腺增生具有较好的抑制作用,95%乙醇提取物作用更好,机理可能与降低血清中睾酮和二氢睾酮的浓度有关,活性成分可能是毛蕊异黄酮为主的黄酮苷元成分。     

睾酮可通过抑制StAR蛋白的表达调节自身的分泌

为了研究睾酮的自分泌调节机制,选取2-3周龄的仔猪睾丸间质细胞为研究材料。不同浓度的睾酮(0、10mg/mL、20mg/mL、50mg/mL、100mg/mL)与间质细胞共孵育48h,更换培养液,加入hCG(50U/mL)孵育4h,收集培养液,用放射免疫法(RIA)测定睾酮、hCG和cAMP的浓度。然后用浓度为50mg/mL的睾酮与胆固醇,5mg/mL;孕烯醇酮,500ng/mL;脱氢表雄酮,500ng/mL;雄烯二酮,500ng/mL和22R-羟胆固醇(3μg/mL)共同孵育间质细胞48h,更换培养液,加入hCG(50U/mL)孵育4h,收集培养液和细胞,用放射免疫法(RIA)测定睾酮,用免疫印迹测定StAR水平。实验结果如下:(1)随着睾酮浓度的增加,睾酮对自身合成的抑制作用逐渐增强,当睾酮浓度为50mg/mL,睾酮分泌、hCG的结合率以及间质细胞内cAMP的浓度分别下降了69.93%、61.24%和52.4%。(2)尽管睾酮抑制了胆固醇和雄烯二酮向睾酮的转化,但对其它几种前体物的转化没有明显影响。(3)睾酮不但抑制了基础水平StAR的表达,而且也抑制了hCG刺激的StAR蛋白的表达,这表明睾酮可以通过抑制StAR蛋白的表达降低自身的合成。     

灵芪胶囊含药血清对K562白血病细胞影响

观察灵芪胶囊含药血清在体外对K562白血病细胞增殖的影响.采用血清药理学方法制备灵芪胶囊含药血清,以不同浓度的含药血清处理体外培养的K562白血病细胞,采用MTT比色法观察灵芪胶囊含药血清对K562细胞增殖的影响,采用Wright-Giemsa染色观察肿瘤细胞形态学变化.不同浓度灵芪胶囊含药血清对K562细胞增殖具有抑制作用,并呈剂量依赖关系.当含药血清作用96h后,其抑制作用开始减弱.高剂量LQC含药血清对K562细胞形态学有明显的影响.灵芪胶囊含药血清具有抑制K562白血病细胞增殖作用,其作用强度与时间-浓度呈正相关,其作用机理可能与其直接细胞毒作用有关.     

天蓝苜蓿含药血清抗白血病K562细胞的体外实验研究

探讨天蓝苜蓿含药血清对白血病细胞株K562细胞增殖抑制的影响,为探索中药治疗白血病提供一定理论依据。方法用不同浓度天蓝苜蓿含药血清处理白血病细胞株K562,24、48、72h后,采用MTT法检测细胞抑制率。结果天蓝苜蓿含药血清能有效的抑制K562细胞增殖,呈时间和剂量依赖关系。细胞发生一系列形态学改变。结论天蓝苜蓿含药血清对K562细胞增殖有一定的抑制作用。     

光周期对环青春期雄性根田鼠血浆睾酮及雌二醇含量的作用

根田鼠母体妊娠期（GP）及哺乳期（LP）光周期处理对环青春期雄体血浆睾酮的作用不显著（P＞0．05）；在断乳期（PP），光周期处理则存在极显著的作用（P＜0．01）。在断乳前的GP及LP，母体长光照处理对子代雄体睾酮有抑制作用；而在PP，长光照处理对子代雄体睾酮则有显著促进作用。在LP，母体长光照处理对雄体血浆雄二醇有显著（P＜0．05）促进作用。而在PP，长光周期处理对雄体血浆雌二醇则有抑制作用。     

荷人鼻咽癌裸鼠血浆MDA,cAMP/cGMP及PSP对其影响的研究

利用BALB/c裸鼠,通过移植人低分化鼻咽癌细胞(CNE-2)复制荷人鼻咽癌(NPC)裸鼠模型,检测荷瘤鼠血浆MDA、cAMP、cGMP和cAMP/cGMP比值,以探讨cAMP/cGMP比值改变的原因和机理;观察云芝糖肽(PSP)对荷人NPC裸鼠的抑瘤作用及对荷瘤鼠血浆MDA、cAMP、cGMP和cAMP/cGMP比值影响,以探讨PSP抑瘤机理。结果发现荷瘤裸鼠血浆MDA(18.25±1.37nmol/m1)与正常裸鼠(10.83±1.18)比,差异非常显著(P<0.01);荷瘤鼠血浆cAMP(71.83±8.51pmol/ml)与正常裸鼠(94.77±4.65)比差异显著(P<0.05);荷瘤鼠血浆cGMP(15.77±0.65pmol/ml)与正常裸鼠(28.20±5.31)比差异非常显著(P<0.01);荷瘤鼠cAMP/cGMP比值(4.55±0.35)与正常鼠(3.37±0.37)比差异非常显著(P<0.01)。用高低浓度PSP对荷人NPC裸鼠进行了三批实验,每批实验均有明显抗癌作用(P<0.01),抑瘤率59.58—95.53％,并可降低荷瘤鼠血浆、组织MDA,提高血浆cAMP、cGMP水平,恢复cAMP/cGMP比值。木实验提示,荷瘤鼠血浆cAMP等降低与MDA的提高有关;PSP对荷人NPC裸鼠有抑瘤作用,其抑瘤机理可能是通过降低荷瘤鼠血浆,组织MDA,提高cAMP、cGMP水平,恢复cAMP/cGMP比值。     

云芝糖肽对裸鼠人肺腺癌抗癌作用的研究

PSP(polysaccharide-peptide)同日本产的PSK(Krestin)是相类似的云芝糖肽。本研究证明,PSP l-2g/kg,连续口服给药15—20天,对裸鼠人肺腺癌有明显的抑制作用,抑制率为50—70％在抑制肿瘤生长的同时,未见有血液系统和体重方面的变化。放射免疫法测定表明PSP不会引起血浆cAMP和cGMP水平的改变,提示其抗癌机制与环核苷酸系统无关。     

红车轴提取物对基质金属蛋白酶的抑制活性

研究质量分数为40%的红车轴黄酮提取物及其含有的4种主要异黄酮对基质金属蛋白酶（MMP-16）的抑制作用. 结果表明, 质量分数为40%的红车轴黄酮提取物以剂量依赖的方式有效抑制MMP-16的活性, 刺芒柄素抑制MMP-16的活性效果较弱而且不是剂量依赖方式, 而鹰嘴豆芽素、 大豆甙元和染料木黄酮不能抑制MMP-16的活性. 红车轴黄酮提取物通过色谱纯化, 得到33种纯化馏分, 其中13号馏分与25号馏分能抑制MM P-16的活性, 并且13号馏分的抑制作用是剂量依赖的.     

乙醇对人工流产新鲜绒毛雌二醇分泌的影响

本工作利用体外灌输技术,观察了三种不同浓度的乙醇(1％,2.5％、5％)对妊娠早期人工流产新鲜胎盘绒毛分泌雌二醇的影响。结果表明,乙醇具有促进雌二醇分泌的作用,但在乙醇剂量和雌二醇水平之间不存在正相关性。提示妊娠妇女经常饮酒或酗酒可能通过破坏胎盘激素内分泌的平衡,从而影响胎儿的正常生长和发育。     

十二时辰中大鼠环核苷酸和白细胞计数的变化

本实验分别在子、丑、寅、卯、辰、巳、午、未、申、酉、戍、亥十二个时辰中,系统地观察了血浆cAMP和cGMP含量以及血液淋巴细胞、嗜中性粒细胞、嗜酸性粒细胞和单核细胞的计数变化,结果表明,它们在十二个时辰中,均反映出阴阳对立和消长的变化规律,在探索“阴阳学说”物质基础的理论和临床上均具有重要意义。     

Insulin trigger, cyclic AMP-dependent activation and phosphorylation of a plasma membrane cyclic AMP phosphodiesterase

Regulation of blood glucose levels by the liver is primarily achieved by the action of two peptide hormones, insulin and glucagon, which bind to specific receptors associated with the hepatocyte plasma membrane. Whilst the molecular action of glucagon at the level of the cell plasma membrane in activating adenylate cyclase is relatively well understood, we know little, if anything, of the molecular consequences of insulin occupying its receptor. We demonstrate here that insulin, at physiologically relevant concentrations, can trigger the cyclic AMP-dependent activation and phosphorylation of a low Km cyclic AMP phosphodiesterase attached to the liver plasma membrane. Such an effect may in part explain the ability of insulin to inhibit the increase in cellular cyclic AMP content that glucagon alone produces by activation of adenylate cyclase. Our observation that basal, intracellular cyclic AMP levels are insufficient to allow insulin to activate the cyclic AMP phosphodiesterase, yet those cyclic AMP levels achieved after exposure of the cells to glucagon are sufficient, gives a molecular rationale to Butcher and Sutherland's proposal that it is necessary to first elevate cellular cyclic AMP levels before they can be depressed by insulin.     

甜菜碱对蛋鸡产蛋期血清激素及环腺苷酸影响的研究

取３００日龄罗曼蛋鸡７６８羽,随机分为２组（每组设４个重复,每个重复９６羽）,在自由采食、饮水和１６ｈ／ｄ光照的条件下,分别饲喂添加０ｍｇ／ｋｇ和７５０ｍｇ／ｋｇ甜菜碱的玉米－豆粕型日粮９１ｄ。结果表明,甜菜碱使蛋鸡血清中促卵泡生成素（ＦＳＨ）、促黄体生成素（ＬＨ）和雌二醇（Ｅ２）含量分别提出了５６．５９％（Ｐ〈０．０１）,２０．７５％（Ｐ〉０．０５）和２２．０９％（Ｐ〈０．０５）;使下丘脑、腺垂     

Knockdown of sAC affects sperm hyperactivation by cAMP-signaling pathway in male rat (Rattus norvegicus)

Soluble adenylyl cyclase (sAC) plays a critical role in male fertility in mammals by regulating sperm hyperactivation. We aimed to study the mechanism of sAC in this phenomenon and to explore potential target sites for male contraception. In this study, in vivo electroporation and rete testis microinjection-mediated short hairpin (sh)RNA plasmids were adopted to silence sAC gene expression in male rats. The results showed that high transfection efficiency (shRNA717, 49.0% and shRNA4205, 65.0%) was achieved by shRNA plasmids injected directly into the rete testis. When the sAC was downregulated, the cyclic adenosine mono-phosphate (cAMP) content and protein phosphorylation level of spermatozoa both declined with a significantly lower hyperactivation rate compared with negative controls. The highest transfection efficiency occurred at 15 d and was obviously time dependent. Bioinformatic and experimental results showed that sAC and tmAC both belong to the AC family and might have analogous functions. ShRNA717 and shRNA4205 were the best targets for the sAC gene, suggesting that they could be candidates for male contraception. Thus, it appears feasible to achieve male contraception by silencing the expression of sAC, affecting sperm hyper-activation via a cAMP-mediated signaling pathway.     

Transduction in taste receptor cells requires cAMP-dependent protein kinase

In taste chemoreception, cyclic adenosine monophosphate (cAMP) appears to be one of the intracellular messengers coupling reception of stimulus to the generation of the response. The recent finding that sweet agents cause a GTP-dependent generation of cAMP poses the question of how this cytosolic messenger acts at the membrane of taste receptor cells. We have shown that cAMP causes a substantial depolarization in these cells. Here we show with whole-cell recordings and inside-out membrane patches that the depolarization caused by cAMP is accounted for by the action of cAMP-dependent protein kinase, which inactivates potassium channels predominantly of 44 pS conductance. Thus, intracellular signalling of the gustatory cells differs from that of olfactory and photoreceptor cells, where cyclic nucleotides control unspecific channels by binding to them rather than by inducing their phosphorylation.     

The universality and biological significance of signal molecules with intracellular-extracellular compatible functions

Generally, cell signal molecules are classified into the extracellular signal molecules (the first messengers) and the intracellular signal ones (the second messengers). Cyclic adenosine monophosphate (CAMP), calcium ions and calmodulin (CaM) are the traditional intracellular messengers, but they are also present in extracellular matrix (ECM). Some of them have been discovered to act as the first messengers through cell surface receptors. Other second messengers, such as cyclic guanosine monophosphate (cGMP), cyclic adenosine diphosphate ribose (cADPR) and annexin, are also found existing outside animal and plant cells. The existence of these messengers with intracellular-extracellular compatible functions in cells may be a regular biological phenomenon. These compatible messengers might be the communication factors between intracellular and extracellular regions or among the cell populations, and are also important in regulating cell development procedure.     

穴位艾灸对男性运动员血清睾酮的影响

根据中医经络理论，运用艾灸相关补肾强壮穴位(本采用关元、足三里穴和肾俞、命门穴交替选用)的方法，对20名男性运动员施灸4周，结果血清睾酮水平明显高于对照组12名男性运动员，提示该方法有助于调整男性运动员雄激素分泌，提高血睾酮水平，进一步提示该法可用以治疗和预防运动性低血睾酮症并且有利于运动疲劳的恢复。     

A research on the relationship between ejaculation and serum testosterone level in men

The purpose of this study is to gain understanding of the relationship between ejaculation and serum testosterone level in men. The serum testosterone concentrations of 28 volunteers were investigated daily during abstinence periods after ejaculation for two phases. The authors found that the fluctuations of testosterone levels from the 2nd to 5th day of abstinence were minimal. On the 7th day of abstinence, however, a clear peak of serum testosterone appeared, reaching 145.7% of the baseline ( P < 0.01). No regular fluctuation was observed following continuous abstinence after the peak. Ejaculation is the precondition and beginning of the special periodic serum testosterone level variations, which would not occur without ejaculation. The results showed that ejaculation-caused variations were characterized by a peak on the 7th day of abstinence; and that the effective time of an ejaculation is 7 days minimum. These data are the first to document the phenomenon of the periodic change in serum testosterone level; the correlation between ejaculation and periodic change in the serum testosterone level, and the pattern and characteristics of the periodic change.     

海藻多糖的实验研究——Ⅱ.鼠尾藻和铜藻多糖对EC109细胞株的抑制和对cAMP-PDE的影响

比较了七种海藻多糖在体外抑制人食管癌细胞株(EC109)的生物活性.结果表明,浓度为100毫克/毫升的不同多糖作用48小时后均出现明显抑制,细胞大部分脱落.抑制率在75～95％之间;当浓度为50毫克/毫升作用后抑制率维持在30％以上;25毫克/毫升以下浓度的鼠尾藻多糖仍表现出显著的抑制效果. 各种多糖对组织环化腺苷酸磷酸二酯酶(cAMP-PDE)的体外抑制表明,唯有褐藻淀粉硫酸酯对兔脑cAMP-PDE活性有明显作用,抑制率达74.5％.