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1.
土壤紧实胁迫对黄瓜根系呼吸代谢的影响   总被引:3,自引:0,他引:3  
用容重分别为1.20和1.55 g· cm-3的土壤进行盆栽试验,研究了土壤紧实胁迫对‘津春4号'黄瓜根系呼吸代谢的影响.结果表明:土壤紧实胁迫条件下,黄瓜根系中丙酮酸脱羧酶、乙醇脱氢酶和乳酸脱氢酶活性显著提高;无氧呼吸主要产物(乙醇、乙醛和乳酸)含量显著升高;参与有氧呼吸的苹果酸脱氢酶、琥珀酸脱氢酶和异柠檬酸脱氢酶活性显著下降,丙酮酸和琥珀酸含量显著提高,苹果酸含量显著下降.说明在土壤紧实胁迫条件下,黄瓜根系的有氧呼吸受到显著抑制,无氧呼吸过程加强.  相似文献   

2.
用容重分别为1.20和1.55 g·cm-3的土壤进行盆栽试验,研究了土壤紧实胁迫对‘津春4号’黄瓜根系呼吸代谢的影响.结果表明: 土壤紧实胁迫条件下,黄瓜根系中丙酮酸脱羧酶、乙醇脱氢酶和乳酸脱氢酶活性显著提高;无氧呼吸主要产物(乙醇、乙醛和乳酸)含量显著升高;参与有氧呼吸的苹果酸脱氢酶、琥珀酸脱氢酶和异柠檬酸脱氢酶活性显著下降,丙酮酸和琥珀酸含量显著提高,苹果酸含量显著下降.说明在土壤紧实胁迫条件下,黄瓜根系的有氧呼吸受到显著抑制,无氧呼吸过程加强.  相似文献   

3.
轻度水分胁迫的小麦幼苗中与呼吸有关的几种酶活性变化   总被引:8,自引:0,他引:8  
轻度水分胁迫使小麦幼苗叶片呼吸升高时,叶中琥珀酸去氢酶和细胞色素氧化酶活性均明显升高;而同样胁迫使根呼吸下降时,根中这两种酶活性均明显下降。叶和根中ATP酶分解活性在胁迫下都明显升高。轻度水分胁迫使叶片过氧化氢酶活性升高。叶中有明显的乙醇酸氧化酶活性,抗旱品种的酶活性较高,胁迫使此酶活性降低。  相似文献   

4.
淹水胁迫对不结球白菜根系生长与呼吸酶活性的影响   总被引:2,自引:0,他引:2  
采用双套盆法,以不结球白菜‘新矮青’和‘新夏青2号’品种为材料,研究了不同时间(1、3、5、恢复7d后)和不同程度淹水处理(根淹、半淹)后不结球白菜根系生长及呼吸代谢的变化规律。结果显示:(1)与对照相比,淹水胁迫下,不结球白菜幼苗根系鲜重、根系长度、根系活力显著下降,且半淹处理的下降幅度大于根淹处理。(2)淹水胁迫下,乳酸脱氢酶(LDH)、乙醇脱氢酶(ADH)活性较对照显著升高,而苹果脱氢酶(MDH)、琥珀酸脱氢酶(SDH)活性显著降低,且半淹处理的降幅大于根淹,淹水5d后与淹水1d后有显著性差异。(3)淹水胁迫下,‘新矮青’乳酸发酵途径弱于‘新夏青2号’,乙醇发酵则相反,导致后者根系中乳酸积累多于前者,细胞质酸化较严重,降低了对淹水胁迫的耐性。研究表明,不结球白菜幼苗期受到淹水胁迫时,其有氧呼吸明显受阻,无氧呼吸代谢被促进,而且随着淹水时间的延长及淹水深度的加深,根系呼吸代谢受到的抑制程度越严重,最终导致根系生长受到抑制。  相似文献   

5.
采用阿利新兰-碘酸雪夫氏反应(AB-PAS)染色法及酶学方法研究了大鳞副泥鳅成熟个体肠道各段黏液细胞分布及消化酶活性。结果表明, 大鳞副泥鳅肠道黏液细胞分为Ⅰ、Ⅱ、Ⅲ和Ⅳ 4种类型。前肠至后肠, 黏液细胞数量逐渐减少。前肠主要分布Ⅲ和Ⅳ混合型黏液细胞, 后肠则以Ⅱ和Ⅳ型酸性黏液细胞为主。肠道胰蛋白酶活性显著高于淀粉酶和脂肪酶。且后肠消化酶活性显著低于前肠和中肠。根据黏液细胞及消化酶活性分布特点, 表明大鳞副泥鳅属于杂食性鱼类, 前肠为其主要的消化吸收场所, 后肠中性黏液细胞的数量较少以及消化酶活性较低, 表明其对食物的消化吸收功能较弱, 与其为辅助呼吸功能的特点相关。  相似文献   

6.
采用营养液水培,研究了根际低氧胁迫下外源亚精胺对2个抗低氧能力不同的黄瓜品种(‘中农八号’和‘绿霸春四号’)根系中多胺含量和呼吸代谢相关酶活性的影响.结果表明,单纯低氧处理下,黄瓜幼苗根系中腐胺、亚精胺和精胺含量显著提高,异柠檬酸脱氢酶(IDH)和琥珀酸脱氢酶(SDH)活性显著降低,乳酸脱氢酶(LDH)、乙醇脱氢酶(ADH)和丙酮酸脱羧酶(PDC)活性显著提高.同时,与抗低氧能力弱的‘中农八号’相比,抗低氧能力强的‘绿霸春四号’根系LDH活性增加幅度较低,ADH活性增加幅度较高,IDH和SDH活性降幅也较小;外源亚精胺能显著提高低氧胁迫下黄瓜幼苗根系中亚精胺和精胺含量,降低腐胺含量;根系中LDH、ADH和PDC活性降低,IDH和SDH活性升高,说明黄瓜幼苗根系中较高的亚精胺、精胺含量可能有利于提高根系有氧呼吸能力,缓解低氧胁迫对植株的伤害.  相似文献   

7.
目的观察静息能量代谢率(resting metabolic rate,RMR)在评价糖皮质激素肾阴虚及肾阳虚证模型中的作用。方法 BALB/c雄性小鼠分为对照组、模型组、金匮肾气丸组、知柏地黄丸组,后三组小鼠均给予含皮质酮的饮用水,对照组给予含1%乙醇的饮用水。采用封闭式流体压力呼吸计测定动物RMR。实验结束,处死小鼠,检测肾周脂肪、附睾脂肪、股四头肌、胫骨前肌重量指数;采用ELISA法检测血清激素水平;肝脏、肾脏组织HE染色观察;检测肝组织丙二醛(malondialdehyde,MDA)含量、琥珀酸脱氢酶(succinate dehydrogenase,SDH)活性、细胞色素c氧化酶(cytochrome-c-oxidase,COX)活性、ATP水平。结果与对照组比较,模型组能量代谢率在实验开始第2天即显著升高,第4天达最高(P0.01),之后逐渐降低,至第66天显著降低(P0.05)。皮质酮造模66 d显著降低小鼠血清甲状腺素(T4)含量,升高脂肪重量指数、降低肌肉重量指数、升高MDA水平、抑制SDH、COX活性及ATP水平。两补肾药均能降低动物死亡率,降低肝组织MDA含量,并且金匮肾气丸能升高模型组第4天及66天的能量代谢率(P0.05),能显著提高肝组织SDH活性、COX活性及ATP水平(P0.01),知柏地黄丸未观察到类似作用。结论静息能量代谢率对评价糖皮质激素肾阴虚/肾阳虚证模型具有一定作用。  相似文献   

8.
为了探讨熊本牡蛎(Crassostrea sikamea)在长期饥饿胁迫下的生理代谢响应,测定了长期饥饿(0~80 d)以及再投喂(90~118 d)状态下熊本牡蛎的耗氧率、排氨率以及肝胰腺组织乳酸脱氢酶、琥珀酸脱氢酶、丙酮酸激酶、超氧化物歧化酶、碱性磷酸酶和溶菌酶的活性。结果表明:长期饥饿下,熊本牡蛎的耗氧率和排氨率极显著降低(P<0.01);随着饥饿时间的延长,熊本牡蛎乳酸脱氢酶、琥珀酸脱氢酶、丙酮酸激酶、超氧化物歧化酶和碱性磷酸酶活性均呈现波动下降的趋势,溶菌酶活性呈现波动上升的趋势;再投喂后熊本牡蛎的耗氧率、排氨率均极显著升高(P<0.01);长期饥饿对熊本牡蛎代谢和免疫功能造成损伤,熊本牡蛎通过降低代谢率和代谢酶的活性应对长期饥饿胁迫。本研究可为海水贝类饥饿胁迫下代谢调节机制的研究提供参考。  相似文献   

9.
研究了生长在正常大气CO2和CO2倍增环境中的盐生植物碱蓬(Suaedasalsa)幼苗呼吸酶活性对KCl和NaCl的反应。结果表明,在CO2倍增(700μl·L-1)和正常大气CO2(350μl·L-1)下,300mmol·L-1KCl和NaCl均能抑制琥珀酸脱氢酶(SDH)和苹果酸脱氢酶(MDH)活性,而异柠檬酸脱氢酶(IDH)活性为NaCl抑制、KCl促进; NaCl和KCl明显抑制细胞色素氧化酶(CO)和光呼吸中乙醇酸氧化酶(GO)、羟基丙酮酸还原酶(HPR)活性; 并指出在KCl胁迫下,CO2使三羧酸循环(TCAC)的运行变慢,NaCl胁迫下使其加快,TCAC运行限速步骤与MDH无关,CO为盐对呼吸代谢影响的重要位点。另外,K+、Na+对蛋白表达的影响有差异,CO2可使盐胁迫下的碱蓬幼苗蛋白表达降低。  相似文献   

10.
氨基酸代谢调控在大鳞副泥鳅应对氨暴露中的作用   总被引:1,自引:0,他引:1  
将大鳞副泥鳅(Paramisgurnus dabryanus)暴露于30 mmol/L NH4Cl溶液中以研究高浓度环境氨对其血浆、肝脏及肌肉组织中游离氨基酸含量的影响。氨暴露会显著影响大鳞副泥鳅血浆、肝脏及肌肉组织中游离氨基酸含量(P0.05)。随着氨暴露时间的延长,大鳞副泥鳅血浆中丙氨酸的含量显著增加,且显著高于对照组(P0.05)。在氨暴露12h后,其肝脏组织中游离谷氨酸含量显著上升(P0.05),而在暴露72h后迅速下降(P0.05)。而游离丙氨酸含量在氨暴露的前24h内基本保持恒定,随后开始显著上升(P0.05)并持续至72h。在氨暴露大鳞副泥鳅12h后,肌肉中游离谷氨酸含量显著上升(P0.05),随后快速下降至初始水平并持续到实验结束(P0.05),且在暴露72h和96h时显著低于对照组(P0.05)。肌肉中游离丙氨酸含量随着氨暴露时间的延长呈现先上升后降低的趋势,并在暴露12h和48h时出现2个峰值,且显著高于对照组(P0.05)。在氨暴露下,其血浆、肝脏及肌肉中游离谷氨酸含量显著降低,且谷氨酰胺含量和谷氨酰胺合成酶活性显著提高,说明在高环境氨条件下,大鳞副泥鳅会利用谷氨酰胺合成酶将谷氨酸和NH_4~+合成无毒的谷氨酰胺以降低氨毒性。随着氨暴露时间的延长,大鳞副泥鳅血浆和组织有明显的丙氨酸累积且游离谷氨酸、精氨酸和脯氨酸含量显著降低,说明其可通过代谢这些特定氨基酸生成丙氨酸以降低体内氨的累积。  相似文献   

11.
为探究塑料袋包装充氧运输胁迫对四指马鲅(Eleutheronema tetradactylum)幼鱼肝、肌肉抗氧化系统的影响以及抗应激剂的生理作用。本研究设置了未经运输的幼鱼30尾作为对照组、不添加任何抗应激剂运输的幼鱼90尾作为空白组、添加维生素C(VC)运输的幼鱼90尾作为维生素C组以及添加谷氨酰胺(Gln)运输的幼鱼90尾作为谷氨酰胺组,在运输实验进行的2 h、6 h以及9 h采样,不同时间点每组各取30尾幼鱼分别采集肝、肌肉样品进行相关指标的测定。测定项目包括:超氧化物歧化酶(SOD)、过氧化氢酶(CAT)、还原型谷胱甘肽(GSH)、丙二醛(MDA)以及总抗氧化能力(T-AOC)。结果显示,运输胁迫使空白组肝和肌肉中SOD活性最终显著(P0.05)高于对照组,而维生素C组和谷氨酰胺组由于抗应激剂的存在而使其最终活性低于对照组;运输胁迫使空白组和维生素C组肝以及肌肉中CAT活性显著(P0.05)升高,最终其活性均显著(P0.05)高于对照组,而谷氨酰胺组最终值与对照组无显著差异(P0.05);运输胁迫使空白组肝和肌肉MDA含量均显著(P0.05)升高,而抗应激剂维生素C和谷氨酰胺明显缓解了这一现象;GSH含量在空白组、维生素C组和谷氨酰胺组的肝与肌肉中均出现了不同的变化趋势,可能与这两种组织所承担的生理功能不同有关;运输胁迫后,空白组肝与肌肉T-AOC值均显著(P0.05)高于对照组,而维生素C组和谷氨酰胺组最终则略高于或等于对照组。本研究分析了运输胁迫下四指马鲅幼鱼抗氧化系统变化规律以及抗应激的作用效果,旨在为其养殖生产提供参考依据。  相似文献   

12.
13.
Air-breathing fish are common in the tropics, and their importance in Asian aquaculture is increasing, but the respiratory physiology of some of the key species such as the striped catfish, Pangasianodon hypophthalmus Sauvage 1878 is unstudied. P. hypophthalmus is an interesting species as it appears to possess both well-developed gills and a modified swim bladder that functions as an air-breathing organ indicating a high capacity for both aquatic and aerial respiration. Using newly developed bimodal intermittent-closed respirometry, the partitioning of oxygen consumption in normoxia and hypoxia was investigated in P. hypophthalmus. In addition the capacity for aquatic breathing was studied through measurements of oxygen consumption when access to air was denied, both in normoxia and hypoxia, and the critical oxygen tension, Pcrit, was also determined during these experiments. Finally, gill ventilation and air-breathing frequency were measured in a separate experiment with pressure measurements from the buccal cavity. The data showed that P. hypophthalmus is able to maintain standard metabolic rate (SMR) through aquatic breathing alone in normoxia, but that air-breathing is important during hypoxia. Gill ventilation was reduced during air-breathing, which occurred at oxygen levels below 8 kPa, coinciding with the measured Pcrit of 7.7 kPa. The findings in this study indicate that the introduction of aeration into the aquaculture of P. hypophthalmus could potentially reduce the need to air-breathe. The possibility of reducing air-breathing frequency may be energetically beneficial for the fish, leaving more of the aerobic scope for growth and other activities, due to the proposed energetic costs of surfacing behavior.  相似文献   

14.
Lungs are the characteristic air-filled organs (AO) of the Polypteriformes, lungfish and tetrapods, whereas the swimbladder is ancestral in all other bony fish. Lungs are paired ventral derivatives of the pharynx posterior to the gills. Their respiratory blood supply is the sixth branchial artery and the venous outflow enters the heart separately from systemic and portal blood at the sinus venosus (Polypteriformes) or the atrium (lungfish), or is delivered to a separate left atrium (tetrapods). The swimbladder, on the other hand, is unpaired, and arises dorsally from the posterior pharynx. It is employed in breathing in Ginglymodi (gars), Halecomorphi (bowfin) and in basal teleosts. In most cases, its respiratory blood supply is homologous to that of the lung, but the vein drains to the cardinal veins. Separate intercardiac channels for oxygenated and deoxygenated blood are lacking. The question of the homology of lungs and swimbladders and of breathing mechanisms remains open. On the whole, air ventilatory mechanisms in the actinopterygian lineage are similar among different groups, including Polypteriformes, but are distinct from those of lungfish and tetrapods. However, there is extreme variation within this apparent dichotomy. Furthermore, the possible separate origin of air breathing in actinopterygian and 'sarcopterygian' lines is in conflict with the postulated much more ancient origin of vertebrate air-breathing organs. New studies on the isolated brainstem preparation of the gar (Lepisosteus osseus) show a pattern of efferent activity associated with a glottal opening that is remarkably similar to that seen in the in-vitro brainstem preparation of frogs and tadpoles. Given the complete lack of evidence for AO in chondrichthyans, and the isolated position of placoderms for which buoyancy organs of uncertain homology have been demonstrated, it is likely that homologous pharyngeal AO arose in the ancestors of early bony fish, and was pre-dated by behavioral mechanisms for surface (water) breathing. The primitive AO may have been the posterior gill pouches or even the modified gills themselves, served by the sixth branchial artery. Further development of the dorsal part may have led to the respiratory swimbladder, whereas the paired ventral parts evolved into lungs.  相似文献   

15.
Effects of sublethal doses of metal (Cu, Cd, Zn) mixtures on the activities of key respiratory enzymes (succinate dehydrogenase, SDH and glyceraldehyde dehydrogenase, GDH) and their recovery following withdrawal of treatments were studied in the freshwater fish O. mossambicus. On the basis of 96 hr LC50 Cu was highly toxic followed by Zn and Cd, and the trimetal combination (Cu+Zn+Cd) was extremely toxic than any other combination; combination of Zn+Cd was least toxic. A significant gradual decrease in SDH with a concomitant increase in GDH activity observed in liver, brain, muscle and gill of animals exposed to metal suggest a metabolic shift from aerobiosis to anaerobiosis due to metal action. Exposed individuals when transferred to metal impoverished water showed an improvement in SDH activity and decline in GDH activity suggesting slow reversal to aerobic metabolism. O. mossambicus needs more time for complete recovery.  相似文献   

16.
Anatomical and histochemical studies have demonstrated that the bulk of autonomic neurotransmission in fish gill is attributed to cholinergic and adrenergic mechanisms (Nilsson. 1984. In: Hoar WS, Randall DJ, editors. Fish physiology, Vol. XA. Orlando: Academic Press. p 185-227; Donald. 1998. In: Evans DH, editor. The physiology of fishes, 2nd edition. Boca Raton: CRC Press. p 407-439). In many tissues, blockade of adrenergic and cholinergic transmission results in residual responses to nerve stimulation, which are termed NonAdrenergic, NonCholinergic (NANC). The discovery of nitric oxide (NO) has provided a basis for explaining many examples of NANC transmissions with accumulated physiological and pharmacological data indicating its function as a primary NANC transmitter.Little is known about the NANC neurotransmission, and studies on neuropeptides and NOS (Nitric Oxide Synthase) are very fragmentary in the gill and the air-breathing organs of fishes. Knowledge of the distribution of nerves and effects of perfusing agonists may help to understand the mechanisms of perfusion regulation in the gill (Olson. 2002. J Exp Zool 293:214-231).Air breathing as a mechanism for acquiring oxygen has evolved independently in several groups of fishes, necessitating modifications of the organs responsible for the exchange of gases. Aquatic hypoxia in freshwaters has been probably the more important selective force in the evolution of air breathing in vertebrates. Fishes respire with gills that are complex structures with many different effectors and potential control systems. Autonomic innervation of the gill has received considerable attention. An excellent review on branchial innervation includes Sundin and Nilsson's (2002. J Exp Zool 293:232-248) with an emphasis on the anatomy and basic functioning of afferent and efferent fibers of the branchial nerves. The chapters by Evans (2002. J Exp Zool 293:336-347) and Olson (2002) provide new challenges about a variety of neurocrine, endocrine, paracrine and autocrine signals that modulate gill perfusion and ionic transport.The development of the immunohistochemical techniques has led to a new phase of experimentation and to information mainly related to gills rather than air-breathing organs of fishes. During the last few years, identification of new molecules as autonomic neurotransmitters, monoamines and NO, and of their multiple roles as cotransmitters, has reshaped our knowledge of the mechanisms of autonomic regulation of various functions in the organs of teleosts (Donald, '98).NO acts as neurotransmitter and is widely distributed in the nerves and the neuroepithelial cells of the gill, the nerves of visceral muscles of the lung of polypterids, the vascular endothelial cells in the air sac of Heteropneustes fossilis and the respiratory epithelium in the swimbladder of the catfish Pangasius hypophthalmus. In addition, 5-HT, enkephalins and some neuropeptides, such as VIP and PACAP, seem to be NANC transmitter candidates in the fish gill and polypterid lung. The origin and function of NANC nerves in the lung of air-breathing fishes await investigation.Several mechanisms have developed in the Vertebrates to control the flow of blood to respiratory organs. These mechanisms include a local production of vasoactive substances, a release of endocrine hormones into the circulation and neuronal mechanisms.Air breathers may be expected to have different control mechanisms compared with fully aquatic fishes. Therefore, we need to know the distribution and function of autonomic nerves in the air-breathing organs of the fishes.  相似文献   

17.
Iron, the prosthetic group of haemoglobin, was found to lower serum glucose levels of diabetic rats. Its regulative mechanism and effects on enzymatic activities of glucose metabolism are still unknown. In this study, the correlation between iron supply and enzymatic activities of glucose metabolism and respiratory chain were evaluated in liver and kidney tissues of alloxan induced-diabetic rats. After FeSO4 and metformin administration, serum samples were collected for serum glucose and fructosamine level measurements. Kidney and liver tissues were excised at the end of the study for assaying enzymatic activities of isocitrate dehydrogenase, succinate dehydrogenase, malate dehydrogenase, NADH-dehydrogenase and cytochrome-c-oxidase. Results showed significantly decreased serum glucose and fructosamine levels in treatment groups and enhanced enzymatic activities of several proteins as compared with the diabetic control group. Therefore, these data suggested that FeSO4 administration could increase the supply of oxygen, enhance enzymatic activities of glucose metabolism and the respiratory chain, accelerate glucose metabolism and consequently decrease serum glucose levels.  相似文献   

18.
Rhinelepis strigosa did not surface for air breathing in normoxic or moderate hypoxic water. This species initiated air breathing when the P io2 in the water reached 22 ± 1 mmHg. Once begun, the air-breathing frequency increased with decreasing P io2. Aquatic oxygen consumption was 21·0 ± 1·9ml O2 kg−1h−1 in normoxic water, and was almost constant during progressive hypoxia until the P io2 reached 23·9 mmHg, considered the critical oxygen tension (Pco2). Gill ventilation increased until close to the P co2 (7·9-fold) as a consequence of a greater increase in ventilatory volume than in breathing frequency. Gill oxygen extraction was 42 ± 5% and decreased with hypoxia, but under severe hypoxia returned to values characteristic of normoxic. The critical threshold for air breathing was coincident with the Pco2 during aquatic respiration. This suggests that the air-breathing response is evoked by the aquatic oxygen tension at which the respiratory mechanisms fail to compensate for environmental hypoxia, and the gill O2 uptake becomes insufficient to meet O2 requirements.  相似文献   

19.
为研究低氧/复氧胁迫对克氏原螯虾(Procambarus clarkii)抗氧化及能量代谢的影响,将克氏原螯虾暴露于(1.0±0.1) mg/L急性低氧胁迫和后续(6.8±0.2) mg/L复氧环境中,于低氧胁迫1h、6h及复氧1h、12h分别采集肝胰腺、鳃和血淋巴,研究低氧/复氧胁迫下克氏原螯虾抗氧化-能量代谢酶的活力变化,分析鳃和肝胰腺组织的超微结构改变。在低氧胁迫下,肝胰腺和血淋巴中SOD酶活力显著下降(P<0.05);复氧以后,肝胰腺、血淋巴及鳃组织中SOD酶活力均出现了显著上升(P<0.05)。SOD酶活力变化可能与复氧过程中超氧阴离子自由基的过量产生有关。在复氧12h后,血淋巴和鳃组织中MDA含量均出现了显著性增加(P<0.01),提示机体细胞在复氧胁迫下产生了脂质过氧化。在低氧胁迫下,肝胰腺、鳃和血淋巴中ACP、AKP酶活力显著上升(P<0.05);在复氧12h后,肝胰腺和鳃组织中ACP酶活力显著降低(P<0.01)。显示低氧/复氧胁迫影响了机体的非特异性免疫应答。在急性低氧胁迫下,肝胰腺、血淋巴与鳃组织中的LDH含量和总ATPase活力均显...  相似文献   

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