长角血蜱若虫发育期20——羟基蜕皮酮含量变化与表皮发生的关系

用高效液相色谱和放射免疫分析对长角血蜱Haemaphysalislongicornis若虫发育期整体蜕皮激素(20-E)含量变化进行了测定,并用扫描电镜对其表皮结构及其发生进行了观察.20-E存在于若虫整个发育期,饥饿、吸血和饱血后前4天,激素水平低(0.71～1.30ng/头);饱血后6天明显增加,此时皮层溶离开始,蜕皮间隙形成;饱血后7天继续增加;饱血后8天,20-E含量达到高峰(8.70ng/头),此时若虫开始沉积新的上表皮;高峰后,20-E含量急剧下降,直到蜕皮前保持低水平,此期内沉积新的原表皮,旧表皮被部分吸收.上述结果显示出20-E含量急剧增加及其高峰分别与启动皮层溶离和新的上表皮沉积相吻合,20-E与新的原表皮沉积无关.     

20-羟基蜕皮酮放射免疫分析法

<正> 放射免疫分析法(RIA)是放射性同位素示踪技术与免疫反应原理相结合的一种体外的超微量分析方法。其特点是灵敏度高、特异性强、精确度好、取样量少、操作简便,不会引起生物体的辐射损伤。这种方法能定量分析毫微克—微微克水平的微量物质。被测物质达二三百种之多,目前已成为生物学和医学研究中不可缺少的手段。 RIA的基本原理是:在一溶液系统中,一定量的放射性同位素标记的抗原(~*Ag)和待测的非标记抗原(Ag)对一定量特异抗体(Ab)的竞争性结合。Ag的量愈大,~*Ag被稀释的程度也愈大,从而~*Ag-Ab     

20-羟基蜕皮酮对蓖麻蚕蛹体液免疫的调节作用(英)

本研究指出20—羟基蜕皮酮(20-OHE)参加蓖麻蚕蛹对大肠杆菌的体液免疫反应。20-OHE的作用方式是多方面的,包括提高血淋巴蛋白质含量,产生抗菌蛋白,增加溶菌酶活性,和激活原酚氧化酶系统。这表明多个免疫控制系统参与蓖麻蚕蛹体液免疫反应的可能性。     

长角血若虫发育期20—羟基皮酮含量变化与表皮发生的关系

用高效液相色谱和放射免疫分析对长角血蜱Haemaphysalis longicornis若虫发育期整体蜕皮激素（20－E）含量变化进行了测定,并用扫描电镜对其表皮结构及其发生进行了观察。20－E存在于菲虫整修发育期,饥饿、吸血和饱血后前4天,激素水平低（0.71－1.30ng/头）;饱血后6天明显增加,此时皮溶离开始,蜕皮间隙形成;饱血后7天继续增加;饱血后8天,20－E含量达到高峰（8.70ng/头）,此时若虫开始沉积新的上表皮;高峰后,20－E含量急剧下降,直到蜕皮前保持低水平,此期内沉积新的原表皮,旧表皮被部分吸收,上述结果显示出20－E含量急剧增加及其高峰分别与启动皮层溶离和新的上表皮沉积相吻合,20－E与新的原表皮沉积无关。     

20-羟基蜕皮酮对棉铃虫免疫系统的影响

20-羟基蜕皮酮(20-hydroxyecdysone,20E)是昆虫生长发育的重要调节激素,其类似物RH2485常作为杀虫剂使用,对昆虫的影响全面而深刻。然而20E对昆虫免疫系统的影响作用至今我们仍了解较少。为探究20E在棉铃虫Helicoverpa armijera生长发育过程中对免疫系统的影响,本研究选取6龄取食期幼虫注射20E,采用半定量RT-PCR检测了24个棉铃虫体液免疫相关基因在脂肪体和血淋巴中的表达变化,并检测了20E对细胞免疫的影响,包括细胞吞噬能力、凋亡状况及细胞密度变化。结果显示20E处理后,在脂肪体和血淋巴中不同免疫基因对20E的响应不同;血细胞密度在处理12 h后增加2倍,24 h后减少近1/2,但其中浆血细胞密度相对增加,细胞间的粘连作用增强,吞噬率提高约15%,凋亡率升高。结果表明,20E对棉铃虫免疫系统有显著影响,其中对体液免疫的影响比较复杂,但对细胞免疫有明显增强作用。     

20-羟基蜕皮酮调控昆虫先天免疫的分子机制研究进展

昆虫先天免疫(innate immunity)包括细胞免疫(cellular immunity)和体液免疫(humoral immunity)。近年来研究表明,作为昆虫生长发育调节的关键激素之一,20-羟基蜕皮酮(20-hydroxyecdysone, 20E)参与调节了昆虫的先天免疫。本文在介绍昆虫免疫机制的基础上,重点阐述20E调控昆虫先天免疫及微生物影响20E滴度的分子调控机制。20E可以激活细胞免疫和体液免疫来对抗外源入侵微生物,而外源微生物的刺激也会通过3-脱氢蜕皮激素-3β-还原酶(3-dehydroecdysteroid-3β-reductase, 3DE-3β-reductase)促进20E滴度升高。20E对昆虫免疫系统有显著影响,其滴度升高可以激活细胞免疫,包括吞噬(phagocytosis)、包被(encapsulation)和结节(nodulation);而对体液免疫的影响则比较复杂,除可以加速黑化作用(menalization)外,对抗菌肽的表达究竟是促进还是抑制尚不明确。研究人员鉴定发现了一些20E调控体液免疫的关键基因,这些基因的作用途径总结起来可以分为3类:(1)依赖于Toll和IMD等先天免疫通路;(2)依赖于胰岛素(insulin)信号途径;(3)依赖于20E信号通路因子BR-C等的直接调控。但这些通路因子究竟是如何互作以及其分子调控机制等都尚不清楚,值得进一步深入探讨。     

蜕皮激素在银盾革蜱生殖滞育中的作用(英文)

用高效液相色谱法和放射免疫测定法测定了银盾革蜱滞育雌虫的合神经节、血淋巴、卵巢和整体中蜕皮激素的含量,并与正常发育的雌虫做比较。结果表明,滞育雌虫血淋巴和卵巢中蜕皮激素的含量在饱血后前10天与正常发育雌虫基本上相同。饱血10天以后,滞育雌虫蜕皮激素的含量下降,较正常发育雌虫少得多。蜕皮激素的缺乏影响了卵母细胞的发育。为阐明蜕皮激素对滞育雌虫的影响,在不同时间向银盾革蜱滞育雌虫体内注入不同剂量的β-蜕皮素。刚饱血者注入大剂量(1.375和10000ng/蜱)的β-蜕皮素引起雌虫死亡。饱血后20—30天,注入一定剂量(50,70,100ng/蜱)的β-蜕皮素可以促进卵黄形成,并解除了雌虫的生殖滞育,但其所产的卵量明显少于正常发育的雌虫。应用外源蜕皮激素解除硬蜱雌虫的生殖滞育现象尚属首次报道。     

双斑恩蚜小蜂寄生对烟粉虱体内保幼激素和20-羟基蜕皮酮含量的影响

用反相高效液相色谱法（RP-HPLC）测定了烟粉虱Bemisia tabaci体内保幼激素和20-羟基蜕皮酮的滴度。结果显示,被双斑恩蚜小蜂Encarsia bimaculata寄生的烟粉虱高龄若虫体内的保幼激素滴度显著高于（P<0.05）对照即未被寄生的高龄若虫,20-羟基蜕皮酮（20-E）滴度显著低于（P<0.05）对照,与未被寄生的低龄若虫滴度差异不显著,说明双斑恩蚜小蜂寄生后可以将烟粉虱高龄若虫的激素含量保持在低龄若虫的水平,从而调节烟粉虱高龄若虫的生长发育。烟粉虱伪蛹和成虫与对照体内保幼激素含量,烟粉虱伪蛹与对照之间20-E含量差异均不显著（P>0.05）。     

硬蜱中蜕皮激素含量的变化(英语)

为阐明蜕皮激素在硬蜱发育和生殖中的作用,用高效液相色谱法(HPLC)和放射免疫测定法测定了银盾革蜱和长角血蜱中饱血和产卵前后雌虫整体、血淋巴、合神经节及卵巢中蜕皮激素含量的变化.此外,还用HPLC测定了长角血蜱的卵和幼虫中蜕皮激素的含量.结果表明:在饱血前雌虫整体中蜕皮激素含量的变化不大,饱血后迅速增加.血淋巴中的蜕皮激素在饱血后第5天(即产卵前1天)达到高峰,可做为产卵的信号.合神经节中蜕皮激素含量的高峰在饱血后第5天,与血淋巴中高峰出现的时间一致,这与神经分泌细胞的分泌活性变化相吻合.从饱血后第3天起,卵巢中蜕皮激素含量增加很快,直到产卵时止,在长角血蜱的卵中也测到α-蜕皮素,来源于卵巢,随胚胎发育进程其含量逐渐增加.卵产出后第4天到第12天,蜕皮激素的含量增加十几倍.     

长角血蜱幼虫中的蜕皮甾类(英文)

本文用放射免疫分析和高效液相色谱法对长角血蜱幼虫中的蜕皮甾类进行了测定。　蜕皮甾类存在于吸血和饱血幼虫,并且随生理时期而变化。吸血期和饱血后前３天,激素含量低（小于 １４． ３５ｐｇ ＥＥ／只）;饱血后５天迅速上升（２９．８７ｐｇ ＥＥ／只）;饱血后７天达到高峰（５６． ０４ｐｇ ＥＥ／只）;高峰后又下降到低水平（１９．３８ ｐｇＥＥ／只）。高峰期的蜕皮甾类主要为两种成分,２０Ｅ和Ｅ（２０Ｅ∶Ｅ＝３．０７∶１）。２０Ｅ可能是幼虫发育中起主要作用的激素。     

QUANTITATIVE VARIATION OF 20-HYDROXYECDYSONE IN THE NYMPH OF DERMACENTOR NIVEUS NEUMANN*

Abstract The variation of 20-hydroxyecdysone (20 E) levels in the unfed, feeding and engorged nymphs of Dermacentor niveus was studied. The results showed that 20 E existed in all stages of nymphal development. There were two peaks. A small peak (2. 34 ng/nymph) appeared in the feeding period (5 days after attachment) which was connected with the fast feeding before dropping from the host, and a big peak (16.17 ng/nymph) in the moulting period (8 days after engorgement). The latter might be correlated with epicuticle deposition. From the 6th day to the 8th day after engorgement, the level of 20 E rose rapidly. Apolysis occurred in this period.     

THE ROLE OF ECDYSTEROIDS IN THE REPRODUCTIVE DIAPAUSE OF DERMACENTOR NIVEUS NEUMANN

Abstract  The ecdysteroid levels in hemolymph, ovary, synganglion and whole body of diapausing female Dermacentor niveus were detected by HPLC, and compared with the results of nondiapausing female. It is revealed that the ecdysteroid levels in hemolymph and ovary of diapausing female are similar basically to that of nondiapausing female in the first few days after engorgement. From the 10th day after engorgement, the ecdysteroid levels of diapausing female decreased and even became distinctly lower than that of nondiapausing female. The paucity of ecdysteroids in these individuals would influence the normal development of oocytes. In order to explore the effect of ecdyateroids on the diapausing female, we injected 20-hydroxyecdysone with different dosages at different time into the ticks, and found that after just complete engorgement the injection with large dosages (10000 and 1375 ng/tick) caused death of the ticks. From 10th to 20th day after engorgement the ecdysteroid levels of diapausing female are lower than that of nondiapausing one before oviposition, the injection with certain dosages 50, 70 and 100 ng/tick> of 20E can accelerate vitellogenesis and terminate reproductive diapause, but the amount of eggs produced by them is less than that produced by nondiapausing female. The termination of diapause in female of ixcdid tick by exogenous ecdysteroids is reported for the first time.     

银盾革蜱的中肠上皮变化与血餐消化

用光学显微镜及电子显微镜对不同生理状况下银盾革蜱Dermacentor niveus Neumann雌虫中肠上皮及血餐消化进行了研究.饿蜱的中肠只由一种干细胞组成,脂滴作为饿蜱营养的贮藏形式.非滞育蜱消化分三个阶段,即第一连续消化阶段,减慢消化阶段及第二连续消化阶段.吸血后中肠上皮共观察到四种细胞类型,即替代细胞、分泌细胞、消化细胞及卵赞原细胞.滞育蜱第一连续消化阶段延长.饱血后60天到120天,消化作用几近停止,为停滞消化阶段.卵黄原细胞的超微结构有明显改变.滞育解除后,开始进行减慢消化阶段及第二连续消化阶段.     

露水草中20－羟基蜕皮甾酮的动态变化

采用ＨＰＬＣ技术对云南产鸭跖草科分属于３个族１０个属的１３种植物中的２０－羟基蜕皮甾酮进行分析,结果表明２０－羟基蜕皮甾酮广泛存在于已分析的该科植物中,但含量除露水草外均甚微,不具有化学分类学的意义。２０－羟基蜕皮甾酮在不同产地和不同生长季节的露水草中的含量变化,则与蝶类昆虫的活动显示有一定的相关性,从而提示２０－羟基蜕皮甾酮有可能是露水草与蝶类昆虫协同进化过程中的具有化学生态学意义的代谢产物     

QUANTITATIVE VARIATION OF ECDYSTEROIDS OF IXODID TICKS

Abstract  In order to explore the role of ecdysteroids in development and reproduction of ixodid ticks, we studied the quantitative variation of ecdysteroids in the hemolymph, synganglion, ovary and whole body of the female ixodid ticks, Dermacentor niveus and Haemaphysalis longicornis , before and after engorgement and oviposition by HPLC and RIA. The ecdysteroid content in eggs of these ticks was determined by HPLC. The results indicated that before engorgement the quantitative variation of ecdysteroids in the whole female body was not significant, but their levels increased rapidly after engorgement. The ecdysteroid titer in hemolymph was peaked on the 5th day after engorgement, which was one day prior to oviposition. It may be regarded as a singnal of oviposition. In the synganglion the peak of ecdysteroid level occurred also on the 5th day after engorgement. This is coincident with the secretory activity of neurosecretory cells of synganglion. From the 3rd day after engorgement until oviposition the ecdysteroid level in the ovary increased rapidly. Ecdysteroids were detected in eggs of H. longicornis too. They stem from ovary and accumulated with the process of embryonic development.     

REGULATORY ROLE OF 20-HYDROXYECDYSONE ON HUMORAL IMMUNITY IN THE PUPAE OF THE INDIAN SILKWORM,PHZLOSAMIA CYNTHIA RICINI*

Abstract The present study shows that 20-hydroxyecdysone(20-OHE) participates in the humoral immune responses of Philosamia Cynthia ricini, either normal or debrained pupae, to the E. coli. The mode of action of 20—-OHE is multiple. It raises hemolymph protein content, makes antibacterial proteins be produced, increases lysozyme activity, and activates prophenoloxidase system. It is possible that several immune control systems are involved.