首页 | 本学科首页   官方微博 | 高级检索  
相似文献
 共查询到20条相似文献,搜索用时 78 毫秒
1.
浅谈高等动物常见的几种应激现象宗效明(河北省阳原县第一中学075800)张艳平(河北省容城小里中学071700)生物体都具有应激性。如植物根的向地生长,茎则背地生长,这是植物对重力发生的应激反应;昆虫中的蝶类白天活动,蛾类夜晚活动,这是昆虫对日光发生...  相似文献   

2.
植物的应激反应和应激蛋白   总被引:1,自引:0,他引:1  
植物的应激反应和应激蛋白王三根(西南农业大学植物生理生化教研室,重庆630716)关键词应激反应,应激蛋白,热休克蛋白自从1962年Ritossa发现果蝇在热击下引起唾液腺染色体发生蓬松现象,并有转录活性以来,关于热休克蛋白(Heatshockpro...  相似文献   

3.
手术或屠宰采取措囊胚(B)、扩张囊胚(EB)。孵出囊胚(HB),置于含10%FCS的GIT液中进行42℃水浴10分钟的热应激和-7℃酒精糟10分钟的低温感受试验。结果,热应激对猪胚的存活率及发育率均无影响(P>0.05);而热应激提高了猪胚对低温的耐受程度,热应激的胚胎再经低温感受试验后,培养24小时的EB(φ<50)、EB(φ≥50)和HB的活细胞数分别较相应的对照组提高35.5%、41.3%和51.1%,差异显著(P<0.05),但在热应激处理液中添加了蛋白合成抑制剂者没有产生这一效果,此结果证明,热应激很可能诱发猪胚内产生抗低温的应激蛋白质,这为进一步研究猪胚胎冷冻和改进猪胚冷冻前处理提供了依据和可能途径。  相似文献   

4.
为了解植物对镉的吸收和迁移特性,用200 μmol/L镉处理蟛蜞菊(Sphagneticola calendulacea)、南美蟛蜞菊(S.trilobata)及其杂交种,研究了其对镉的吸收、迁移与分布的差异。结果表明,随着镉处理时间的延长,3种植物茎和叶中的镉含量逐渐上升,叶片的镉含量逐渐与茎相当,而根部的镉含量一直是最高的;整株水平上,杂交种的镉含量一直是最高的。恢复生长后,3种植物根中镉含量均呈下降趋势,杂交种(50.4%)>蟛蜞菊(35.8%)>南美蟛蜞菊(33.7%)。镉在3种植物的叶位分布模式在去镉前后没有明显的变化,杂交种更偏向将重金属镉积累于幼叶和成熟叶中。3种植物从叶脉、叶脉间隙到叶片边缘的镉含量逐渐下降,南美蟛蜞菊叶脉的镉含量(2 766.3 μg/kg)最高。可见,杂交种对镉的吸收和转运转移能力高于双亲,预示其在未来应用于植物修复中具有更大的潜力。  相似文献   

5.
慢性应激对大鼠海马锥体细胞形态结构的效应   总被引:16,自引:0,他引:16  
为研究慢性应激相关精神障碍的发病机制,采用尼氏(Nissl)染色法、高尔基(Golgi)镀染法和透射电镜技术,探讨慢性应激对大鼠海马CA1、CA3区锥体细胞形态结构的效应.结果显示应激组大鼠海马CA1区锥体细胞形态结构较对照组无明显变化.应激组海马CA3区锥体细胞数(35.14±3.85)较对照组(38.74±3.54)显著减少(P<0.05);顶树突的总长度(155.67 μm±33.32 μm)较对照组(195.63 μm±34.61 μm)显著缩短(P<0.05);应激组大鼠海马CA3区锥体细胞出现超微结构的改变,包括细胞固缩、体积缩小、核膜皱缩、线粒体变性和粗面内质网模糊不清.这提示海马CA3区锥体细胞形态结构的改变,可能是慢性应激相关精神障碍的病理生理基础.  相似文献   

6.
目的就各类压力应激荷瘤动物模型的造模方法进行综述,对其特点进行评述,并分析了压力应激在肿瘤发生发展中的作用机制。方法应用计算机检索PubMed数据库(2000/2013),以“stress,animalmodel,tumor”为检索词;检索中国知识资源总库(2000~2013)、重庆维普数据库(2000~2013)、万方数据库(2000~2013)三大中文期刊数据库,以“应激,动物模型,肿瘤”为检索词。文章所述内容需与应激动物模型的建立、应用、评价,及压力应激与肿瘤的关系等方面研究密切相关,排除重复性研究。结果共收集596篇关于应激动物模型的文献,中文156篇,英文440篇。阅读标题和摘要进行初筛,排除发表时间较早、重复及类似的研究,纳入30篇符合标准的文献。结论压力应激与肿瘤研究领域为进一步从抗焦虑、抑郁等角度筛选抗肿瘤药物提供参考。  相似文献   

7.
目的:探讨冷束缚应激大鼠血浆及胃黏膜中β-内啡肽(β-endorphine)的变化及作用。方法:制作大鼠冷束缚应激模型,以放免法测定应激0,1/4,2,8h血浆及胃黏膜中β-内啡肽的含量,同时测定胃液pH,胃黏膜溃疡指数(UI),另设两预处理组,分别于应激前15分钟用纳洛酮(1.6mg/kg)和等容量生理盐水颈静脉注射,测定其UI及胃液pH,结果:整个应激过程中血浆及胃黏膜中β-内啡肽的含量无显著变化(P>0.05),应激各组胃黏膜UI均显著高于未应激组(P<0.01),应激15分钟组胃液pH显著高于未应激组(P<0.01),临终前(应激8h组)胃液pH显著高于对照组(P<0.05),阻断阴UI及胃液pH较对照组均无显著变化(P>0.05),结论:应激过程中血浆及胃黏膜β-内啡肽含量稳定,阻断β-内啡肽不影响胃液pH及UI,外周β-内啡肽变化对应激所致胃黏膜损伤可能不起重要作用。  相似文献   

8.
应激诱发抑郁症机制的研究进展   总被引:19,自引:0,他引:19  
慢性应激或长期使用外源性应激激素糖皮质类固醇,可以引起机体神经系统功能失调,诱导抑郁、学习和记忆障碍、衰老过程加速等。其中,应激激素对海马的选择性损伤是导致这些疾患发展的关键原因。其表现为海马出现糖皮质激素(GC)受体下调、神经元萎缩甚至缺失等退行性变化。其机制可能与GC及继发性释放的兴奋性氨基酸(EAAs)协同作用,最终使神经营养因子(如NGF)表达低下有关。本文就慢性应激诱发抑郁症机制的研究进展进行综述。  相似文献   

9.
卞劲松  王幼林 《生理学报》1997,49(5):526-530
本文比较了在制动应激过程中正常及阿霉素心肌损伤大鼠心室电稳定性(VES)的变化间的差异。应激各时程,ivgtt乌头碱(0.8μg/min),心肌损伤大鼠出现心律失常的潜伏期均较正常鼠明显缩短,说明其较正常大鼠更易发生心律失常。正常大鼠随应激时程的延长,VES变化表现为先降后升,而阿霉素大鼠制动2h,室速、室颤潜伏期及其持续时间虽也显著缩短,但制动8h心律失常发生却无明显改变,提示持续制动应激对正常  相似文献   

10.
为研究热应激及恢复对齐口裂腹鱼(Schizothorax prenanti)机体损伤、非特异性免疫功能和细胞凋亡的影响,测定了热应激前(19℃,对照组)、热应激(27℃,0、2h、4h、8h、12h,实验组)及恢复适温6h后(19℃,恢复组)的非特异性免疫相关生理生化指标及细胞凋亡率。结果表明,超氧化物歧化酶(Superoxide dismutase,SOD)在应激0、4h、8h、12h后活性上升,应激0和12h与应激前差异极显著(P<0.01);髓过氧化物酶(Myeloper oxidase,MPO)在热应激4h达到最大值;谷草转氨酶(Glutamic-oxalacetic transaminase,GOT)的活性实验组与对照组差异不显著,恢复6h后GOT活性极显著高于对照组(P<0.01);谷丙转氨酶(Glutamic-pyruvic transaminase,GPT)在应激0、4h、12h和恢复到适温6h后的活性极显著高于对照组(P<0.01);丙二醛(Malondialdehyde,MDA)含量在热应激2h、4h和12h时极显著高于对照组(P<0.01),8h时显著高于应激前(P<0.05),应激12h MDA含量达到最大值,恢复6h后MDA含量恢复至应激前水平(P<0.05);补体3(Complement 3,C3)含量升高,在热应激12h时显著高于对照组(P<0.05),恢复6h C3含量下降,与对照组差异不显著(P>0.05)。持续27℃热应激不同时间后,各实验组的细胞凋亡率都显著高于对照组(P<0.05),且在处理4h时细胞凋亡率达到最高值(52.42%),恢复19℃ 6h后细胞凋亡率显著降低(P<0.05)。研究表明,持续27℃热应激改变了机体非特异性免疫力,导致鱼体出现炎症,损伤细胞,恢复到适温后,鱼体各项机能逐渐恢复。研究结果可为深入研究齐口裂腹鱼高温适应调控机理提供基础数据,也为齐口裂腹鱼养殖、运输等过程中的温度控制提供科学依据。  相似文献   

11.
Plant hormones, in addition to regulating growth and development, are involved in biotic and abiotic stress responses. To investigate whether a hormone signalling pathway plays a role in the plant response to the heavy metal cadmium (Cd), gene expression data in response to eight hormone treatments were retrieved from the Genevestigator Arabidopsis thaliana database and compared with published microarray analysis performed on plants challenged with Cd. Across more than 3000 Cd-regulated genes, statistical approaches and cluster analyses highlighted that gene expression in response to Cd and brassinosteroids (BR) showed a significant similarity. Of note, over 75% of the genes showing consistent (e.g. opposite) regulation upon BR and Brz (BR biosynthesis inhibitor) exposure exhibited a BR-like response upon Cd exposure. This phenomenon was confirmed by qPCR analysis of the expression level of 10 BR-regulated genes in roots of Cd-treated wild-type (WT) plants. Although no change in BR content was observed in response to Cd in our experimental conditions, adding epibrassinolide (eBL, a synthetic brassinosteroid) to WT plants significantly enhanced Cd-induced root growth inhibition, highlighting a synergistic response between eBL and the metal. This effect was specific to this hormone treatment. On the other hand, dwarf1 seedlings, showing a reduced BR level, exhibited decreased root growth inhibition in response to Cd compared with WT, reversed by the addition of eBL. Similar results were obtained on Brz-treated WT plants. These results argue in favour of an interaction between Cd and BR signalling that modulates plant sensitivity, and opens new perspectives to understand the plant response to Cd.  相似文献   

12.
The present study highlights the protective role of β-aminobutyric acid (BABA) in alleviating cadmium (Cd) stress in soybean. Proteomic analyses revealed that out of 66 differentially abundant protein spots in response to Cd challenge, 17 were common in the leaves of BABA-primed and non-primed plants. Oxygen-evolving enhancer protein 1 and ribulose bisphosphate carboxylase small chain 1 were detected in increase abundance in both groups of leaves. Among the 15 commonly decreased protein spots, the relative intensity levels of heat shock cognate 70-kDa protein, carbonic anhydrase, methionine synthase, and glycine dehydrogenase were partially restored after BABA treatment. Moreover, BABA priming significantly enhanced the abundance of the defense-related protein peroxiredoxin and glycolytic enzymes in response to Cd exposure. Additionally, the impact of Cd on the physiological state of BABA-primed and non-primed plants was analyzed using a biophoton technique. The finding of comparatively low biophoton emission in BABA-primed leaves under Cd stress indicates that these plants experienced less oxidative damage than that of non-primed plants. Proteomic study coupled with biophoton analysis reveals that BABA pretreatment helps the plants to combat Cd stress by modulating plants' defence mechanism as well as activating cellular detoxification system to protect the cells from Cd induced oxidative stress damages.  相似文献   

13.
14.
The effects of cadmium (Cd) on cellular proteolytic responses were investigated in the roots and leaves of tomato (Solanum lycopersicum L., var Ibiza) plants. Three-week-old plants were grown for 3 and 10 days in the presence of 0.3–300 μM Cd and compared to control plants grown in the absence of Cd. Roots of Cd treated plants accumulated four to fivefold Cd as much as mature leaves. Although 10 days of culture at high Cd concentrations inhibited plant growth, tomato plants recovered and were still able to grow again after Cd removal. Tomato roots and leaves are not modified in their proteolytic response with low Cd concentrations (≤3 μM) in the incubation medium. At higher Cd concentration, protein oxidation state and protease activities are modified in roots and leaves although in different ways. The soluble protein content of leaves decreased and protein carbonylation level increased indicative of an oxidative stress. Conversely, protein content of roots increased from 30 to 50%, but the amount of oxidized proteins decreased by two to threefold. Proteolysis responded earlier in leaves than in root to Cd stress. Additionally, whereas cysteine- and metallo-endopeptidase activities, as well as proteasome chymotrypsin activity and subunit expression level, increased in roots and leaves, serine-endopeptidase activities increased only in leaves. This contrasted response between roots and leaves may reflect differences in Cd compartmentation and/or complexation, antioxidant responses and metabolic sensitivity to Cd between plant tissues. The up-regulation of the 20S proteasome gene expression and proteolytic activity argues in favor of the involvement of the 20S proteasome in the degradation of oxidized proteins in plants. This paper is dedicated to Nathalie Galtier (1964–2005), who was senior researcher at the INRA Research Center, Villenave d’Ornon, France.  相似文献   

15.
Calcium (Ca) plays important role in plant development and response to various environmental stresses. However, its involvement in mitigation of heavy metal stress in plants remains elusive. In this study, we examined the effect of Ca (50 mM) in controlling cadmium (Cd) uptake in mustard (Brassica juncea L.) plants exposed to toxic levels of Cd (200 mg L−1 and 300 mg L−1). The Cd treatment showed substantial decrease in plant height, root length, dry weight, pigments and protein content. Application of Ca improved the growth and biomass yield of the Cd-stressed mustard seedlings. More importantly, the oil content of mustard seeds of Cd-stressed plants was also enhanced with Ca treatment. Proline was significantly increased in mustard plants under Cd stress, and exogenously sprayed Ca was found to have a positive impact on proline content in Cd-stressed plants. Different concentrations of Cd increased lipid peroxidation but the application of Ca minimized it to appreciable level in Cd-treated plants. Excessive Cd treatment enhanced the activities of antioxidant enzymes superoxide dismutase, ascorbate peroxidase and glutathione reductase, which were further enhanced by the addition of Ca. Additionally, Cd stress caused reduced uptake of essential elements and increased Cd accumulation in roots and shoots. However, application of Ca enhanced the concentration of essential elements and decreased Cd accumulation in Cd-stressed plants. Our results indicated that application of Ca enables mustard plant to withstand the deleterious effect of Cd, resulting in improved growth and seed quality of mustard plants.  相似文献   

16.
This paper aims to develop our understanding of the effect of cadmium (Cd) on Impatiens glandulifera, a recently identified potential Cd hyperaccumulator. Impatiens glandulifera plants were exposed to three concentrations of Cd (20, 60 and 90 mg/kg) and were sampled at two timepoints (one and seven days) to investigate the stress response of I. glandulifera to Cd. Cd can induce oxidative stress in plants, triggering overproduction of reactive oxygen species (ROS). The level of activity of catalase (CAT) and ascorbate peroxidase (APX), two crucial antioxidant enzymes responsible for detoxifying ROS, were found to increase in a concentration dependent manner. Though there was no change observed in the level of superoxide dismutase (SOD) activity, the activity of glutathione S-transferase (GST), involved in detoxifying and sequestering Cd, increased after exposure to Cd. Cd did not appear to impact the levels of proline and photosynthetic pigments, indicating the plants weren't stressed by the presence of Cd. These results suggest that the rapid response observed in enzyme activity aid the efficacious mitigation of the toxic effects of Cd, preventing significant physiological stress in I. glandulifera.  相似文献   

17.
18.
Genotypic variation of the response to cadmium toxicity in Pisum sativum L   总被引:13,自引:0,他引:13  
This work evaluates the (cor-)relations between selected biochemical responses to toxic Cd and the degree of Cd sensitivity in a set of pea genotypes. Ten genotypes were analysed that differ in their growth response to Cd when expressed as root or shoot tolerance indices (TIs). Concentrations of non-protein thiols (NPTs) and malondialdehyde (MDA), activity of chitinase, peroxidase (POX), and catalase significantly increased in all pea genotypes treated with Cd. Cd-sensitivity of genotypes was correlated with relative increases in MDA concentration as well as activities of chitinase and POX, suggesting similar Cd stress effects. Activities of ascorbate peroxidase (APX) decreased, but concentrations of glutathione (GSH) increased in the less Cd-sensitive genotypes. Differences in root and leaf contents of Cd revealed no correlation with TI, metabolic parameters, and enzyme activities in Cd-treated plants, respectively, except that shoot Cd concentration positively correlated with shoot chitinase activity. Toxic Cd levels inhibited uptake of nutrient elements such as P, K, S, Ca, Zn, Mn, and B by plants in an organ- and genotype-specific manner. Cd-sensitivity was significantly correlated with decreased root Zn concentrations. The results show both similarities, as well as distinct features, in Cd toxicity expression in genotypes of one species, suggesting that independent and multi-factorial reactions modulate Cd sensitivity on the low-tolerance level of plants. The study illustrates the biochemical basis of earlier detected genotypic variation in Cd response.  相似文献   

19.
Tulbaghia violacea Harv. (Alliaceae) is one of the few medicinal plants that is also frequently used as a leafy vegetable. Application of cadmium (Cd) at 2 and 5 mg/L to T. violacea plants of various sizes (small 8–10 g, medium 16–20 g, large 80–95 g) elicited a difference in growth response, Cd accumulation and micronutrient distribution. Application of Cd up to 5 mg/L had no significant effect on growth parameters of large-sized plants while leaf length and fresh weight of leaves of the medium-sized plants decreased with application of Cd at 2 mg/L, and 5 mg/L. Cadmium significantly decreased the number of leaves in small-sized plants. Small plants accumulated more Cd in the leaves than medium or large-sized plants. Application of Cd at 2 and 5 mg/L lowered the leaf Cu, Fe, Mo and Zn contents in small and medium-sized plants but had no effect on the micronutrients in large-sized plants. This study indicates that T. violacea has the ability to accumulate Cd. In addition, plant size plays an important role with regards to Cd accumulation and elemental distribution. The results presented in this study include the first report on the nutritional status of T. violacea leaves.  相似文献   

20.
植物对重金属镉的耐受机制   总被引:48,自引:0,他引:48  
镉离子(Cd^2+)具有强植物毒性,抑制植物生长,甚至使植物死亡。由于长期的环境选择和适应进化,植物发展出耐受机制,可减轻或避免Cd^2+的毒害。硫转运蛋白、硫还原相关酶类以及半胱氨酸、谷胱甘肽和植物螯合肽合成基因的表达受Cd^2+调控。同时这些基因的过表达也能提高植物对Cd^2+的耐性。植物抗氧化系统对Cd^2+胁迫诱发的活性氧的清除作用,具转运Cd^2+活性的质膜转运蛋白促进Cd^2+经共质体途径向木质部运输、装载,而后随蒸腾流向地上部迁移,具转运Cd^2+活性的液泡膜转运蛋白促进Cd^2+进入液泡的隔离作用,都在植物对Cd^2+的耐性中起作用。  相似文献   

设为首页 | 免责声明 | 关于勤云 | 加入收藏

Copyright©北京勤云科技发展有限公司  京ICP备09084417号