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1.
目的和方法:血管内皮生长因子(vascularendothelialgrowthfactor,VEGF)是新近确定的一种特异作用于血管内皮细胞的活性肽。最近发现正常心肌细胞可表达VEGF,高血压肥大心脏心肌VEGF及基因表达增强,但对运动性心肌肥大时的变化尚不清楚。本实验采用免疫组化和分子杂交方法,对游泳运动10周大鼠稳定期肥大心脏心肌VEGF及其基因表达进行研究。结果:WistarKyoto(WKY)大鼠、自发性高血压大鼠(spontaneouslyhypertensiverats,SHR)和运动大鼠心肌细胞浆内均有特异性VEGF染色颗粒,但运动大鼠心肌细胞胞浆内染色颗粒增加最明显。Northern分子杂交结果表明三组大鼠心肌均有VEGFmRNA表达,其中SHR表达最强,运动大鼠比WKY大鼠增强,但低于SHR。结论:目前对这一结果的生理意义还不清楚,推测可能与心肌肥大时细胞间质血管增生有关。  相似文献   

2.
SHRsp内脏阻力血管平滑肌钙通道动力学特征   总被引:3,自引:0,他引:3  
用膜片箝全细胞钡电流方式比较成年雄性卒中易感型自发性高血压大鼠(SHRsp)及正常大鼠(Wistar)肠系膜动脉A4-A5分支阻力血管平滑肌电压依赖性钙通道的动力学特性。结果发现:1)两种大鼠该段均存在有L型与T型钙通道。2)峰值电流(peakIBa2+)幅度和密度SHRsp均大于Wistar大鼠。3)通道激活时间常数(τa)SHRsp小于Wistar大鼠,失活时间常数(τi)于箝制电压(HP)=-40mV时,两种大鼠无区别,HP=-80mV时,SHRsp显著大于Wistar。4)和Wistar大鼠相比较,SHRsp的稳态激活曲线(D∞)与稳态失活曲线(F∞),均呈现左移。SHRsp肠系膜动脉阻力血管平滑肌电压依赖性钙通道的如此特征更有利于胞外钙离子进入胞内。而关于内脏阻力血管的实验结果迄今鲜有报道。  相似文献   

3.
目的和方法:血管内皮生长因子(vascularendothelialgrowthVEGF)是新近确定的一种特异作用血管内皮细胞的活性肽。最近发现正常心肌细胞可表达VEGF高血压肥大心脏恼肌VEGF及其因表达增强,但对运动性心肌肥大时的变化尚不清楚,本实验采用免疫组分和分子杂交方法,对游泳运动10周大鼠稳定期肥大心脏心肌VEGF及其基因表达进行了研究,结果:WistarKyoto(WKY)大鼠,自发  相似文献   

4.
利钾尿肽 (kaliureticpeptide ,KP)是近年发现的与心钠素 (atrialnatriureticpeptide ,ANP)源于同一前体的具有 2 0个氨基酸的生物活性多肽。它不仅具有和心钠素一样的利尿、舒张血管、抑制肾素一血管紧张素系统的作用 ,还具有抑制心肌Na -K ATP酶的作用 ,在调节机体血压和高血压发病中有重要意义。我们最近的研究发现 ,自发性高血压大鼠 (spontaueouslyhypertensiverat,SHR)循环血液内的KP水平显著高于正常对照组Wistar Kyoto大鼠 (W…  相似文献   

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研究运动逆转高血压肥大心脏心肌肌球蛋白重链(myosin heavy chain ,MHC)异型改变的分子机制。方法:采用Northern 分子杂交方法对自发性高血压大鼠(spontaneously hypertensive rats,SHR) 游泳运动10 周后心肌MHC基因表达进行比较研究。结果:游泳SHR收缩压和舒张压分别比安静SHR 降低22 % 和25% (P< 0.01) 。左心室重/体重(LVW/BW)比值两组间无明显差异(P> 0.05)。游泳SHR 心肌αMHCmRNA表达比安静SHR增强17% ,βMHCmRNA 表达降低26 % ,α/βMHC基因表达比值提高59 % 。结论:运动逆转高血压肥大心脏心肌MHC同型异构体转变的调控机制可发生在基因转录水平上  相似文献   

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本文用放射性配基[3H]8-OH-DPAT的结合实验显示,自发性高血大鼠(SHR)海马、下丘脑及低位脑干的5-HT1A受体结合位点数较正常Wistar大鼠为多,其中以海马最为显著;脑干的5-HT1A受体虽较正常Wistar大鼠多,但不太明显。SHR下丘脑中5-HT1A受体除结合位点较正常Wistar鼠多外,亲和力也有增大。以上结果表明,SHR与正常Wistar大鼠之间各脑区中5-HT1A受体的差别可能与高血压病的发生有关。  相似文献   

7.
观察自发性高血压大鼠(SHR)血管平滑肌细胞(VSMCs)的生长曲线、c-fos原癌基因表达和c-fos基因酶切图谱的情况,与对照组京都维斯特大鼠(WKY)进行对比。结果显示,在小牛血清作用下SHR的VSMCs生长速率和c-fos原癌基因表达明显大于WKY;c-fos原癌基因限制性内切酶片段长度多态性(RFLP)分析表明,经BamH I或EcoR I酶切后的SHR-WKY的酶切图谱一致,同时也未发  相似文献   

8.
观察自发性高血压大鼠(SHR)血管平滑肌细胞(VSMCs)的生长曲线、c-fos原癌基因表达和c-fos基因酶切图谱的情况,与对照组京都维斯特大鼠(WKY)进行对比.结果显示,在小牛血清作用下SHR的VSMCs生长速率和c-fos原癌基因表达明显大于WKY;c-fos原癌基因限制性内切酶片段长度多态性(RFLP)分析表明,经BamHⅠ或EcoRⅠ酶切后的SHR和WKY的酶切图谱一致,同时也未发现SHR的fos基因扩增现象.提示,VSMCs的异常增殖和c-fos原癌基因的表达异常与高血压的形成有关,而c-fos原癌基因的过度表达可能是由于某些与基因转录调控有关的因素异常所致.  相似文献   

9.
Jiang ZS  Yang YZ  Zhao W  Pang YZ  Liu NK  Tang CS 《生理学报》2000,52(3):211-214
研究碱性成纤维细胞生长因子(basic fibroblast growth factor,bFGF)对自发性高血压大鼠(SHR)和WKY大鼠血管一氧化氮(NO)及内皮素生成的影响。取SHR和WKY大鼠主动脉制成血管薄片,以10、100ng/ml bFGF(终浓度)分别孵育6h,测定血管组织中一氧化氮合酶(NOS)活性及孵育液中亚哨酸盐(NO2)和内皮素含量。结果显示:SHR主动脉组织NOS活性较W  相似文献   

10.
目的:研究运动地高血压肥大心脏心肌有和次级应答基因表达的影响。方法:Eorthern分子杂交方法对游泳运动10周后自发性高血压大鼠心肌初级应答基因c-fosmRNA和次级应答基因心钠素mRNA的表达进行比较研究。结果:游泳SHR收缩压和坟分别比安静SHR降低22%和25%,但左心室重/体重比值两组间无明显差异。SHR最后一次游泳24h后,心肌c-fosmRNA表达与安静SHR相比无明显差异,但两组  相似文献   

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It has now been over twenty years since a novel herpesviral genome was identified in Kaposi's sarcoma biopsies. Since then, the cumulative research effort by molecular biologists, virologists, clinicians, and epidemiologists alike has led to the extensive characterization of this tumor virus, Kaposi's sarcoma-associated herpesvirus(KSHV; also known as human herpesvirus 8(HHV-8)), and its associated diseases. Here we review the current knowledge of KSHV biology and pathogenesis, with a particular emphasis on new and exciting advances in the field of epigenetics. We also discuss the development and practicality of various cell culture and animal model systems to study KSHV replication and pathogenesis.  相似文献   

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Comprises species occurring mostly in subtidal habitats in tropical, subtropical and warm-temperate areas of the world. An analysis of the type species, V. spiralis (Sonder) Lamouroux ex J. Agardh, a species from Australia, establishes basic characters for distinguishing species in the genus. These characters are (1) branching patterns of thalli, (2) flat blades that may be spiralled on their axis, (3) width of the blade, (4) primary or secondary derivation of sterile and fertile branchlets and (5) position of sterile and fertile branchlets on the thalli. Application of the latter two characters provides an important basic method for separation of species into three major groups. Osmundaria , a genus known only in southern Australia, was studied in relation to Vidalia , and its separation from the Vidalia assemblage is not accepted. Species of Vidalia therefore are transferred to the older genus name, Osmundaria. Two new species, Osmundaria papenfussii and Osmundaria oliveae are described from Natal. Confusion in the usage of the epithet, Vidalia fimbriala Brown ex Turner has been clarified, and Vidalia gregaria Falkenberg, described as an epiphyte on Osmundaria pro/ifera Lamouroux, is revealed to be young branches of the host, Osmundaria prolifera.  相似文献   

17.
Fifteen chromosome counts of six Artemisia taxa and one species of each of the genera Brachanthemum, Hippolytia, Kaschgaria, Lepidolopsis and Turaniphytum are reported from Kazakhstan. Three of them are new reports, two are not consistent with previous counts and the remainder are confirmations of very scarce (one to four) earlier records. All the populations studied have the same basic chromosome number, x = 9, with ploidy levels ranging from 2x to 6x. Some correlations between ploidy level, morphological characters and distribution are noted.  相似文献   

18.
肝癌中HBV和HCV基因和抗原的分布及意义   总被引:1,自引:0,他引:1  
采用原位分子杂交方法检测HCV RNA及HBV X基因;采用免疫组织化学方法研究HCV核心抗原,非结构区C33c抗原及HBxAg在肝细胞肝癌中的定位及分布.结果表明(1)HCV RNA、HBV X基因在肝细胞肝癌组织检出率分别为40%(55/136)和82%(112/136).HCV RNA定位于癌细胞的胞浆内,阳性细胞呈散在、灶状及弥漫分布三种形式;HBV X基因在肝癌细胞中的分布呈胞浆型、核型及核浆型,阳性细胞也呈上述三种分布形式;(2)HCV C33c抗原、核心抗原在肝细胞肝癌中的阳性率为81%(133/164)及86%(141/164).C33c抗原定位于癌细胞及肝细胞的胞浆内;核心抗原既定位于癌细胞核中,又可定位于胞浆中.C33c抗原阳性细胞以灶状分布为主;而核心抗原阳性细  相似文献   

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For a plant selection model with frequency-independent viabilities, fertilities and selfing rates, it is shown that apart from global fixation, for certain parameter combinations a protected polymorphism and facultative fixation (either allele may become fixed according to initial frequencies) may both occur. Facultative fixation requires different selling rates for the dominant and recessive type. Protection of the polymorphism requires resource allocation for male and female function. In this connection the problem of purely genetically caused population extinction is discussed.
For general frequency dependence and regular segregation, the chances for establishment of a completely recessive gene are compared to those of a completely dominant gene. It is proven that the process of establishment of the recessive gene, despite a fitness advantage, may be considerably endangered by drift effects if random mating prevails. The recessive gene may reach the same effectivity in establishment as a dominant gene, only if the recessive homozygote mates exclusively with its own type during the period of establishment.  相似文献   

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