共查询到16条相似文献，搜索用时 187 毫秒
1.
将大鳞副泥鳅(Paramisgurnus dabryanus)分别暴露于 30 mmol/L NH4Cl 溶液和空气中, 以评价氨和空气暴露对其肝脏抗氧化能力的影响。结果显示, 氨暴露并未引起大鳞副泥鳅肝脏超氧化物歧化酶(superoxide dismutase, SOD)活性的显著变化, 仅空气暴露 12 h 后, 大鳞副泥鳅肝脏 SOD 活性显著高于对照组(P<0.05)。氨和空气暴露均显著降低了大鳞副泥鳅肝脏过氧化氢酶 (catalase, CAT) 活性 , 且在暴露 72 h 后升高 (P<0.05) 。丙二醛 (malondialdehyde, MDA)及脂质过氧化物(lipid peroxide, LPO)含量在氨和空气暴露组中均呈现先显著上升后下降的趋势。氨和空气暴露对大鳞副泥鳅肝脏谷胱甘肽-S 转移酶(glutathione S-transferase, GST)活性、谷胱甘肽(glutathione, GSH)含量和总抗氧化能力(total antioxidant capacity, T-AOC)无显著影响(P>0.05), 但谷胱甘肽过氧化物酶 (glutathione peroxidase, GSH-Px)活性均明显降低, 乙酰胆碱酯酶(acetylcholin esterase, AChE)活性均显著上升。综上所述, 在氨和空气暴露的初期, 大鳞副泥鳅体内出现了明显的氧化反应; 而在暴露一段时间后, 体内的氧化反应受到了明显的抑制, 大鳞副泥鳅肝脏中 SOD、CAT、GST 及 GSH-Px 等抗氧化酶系统并未被成功激活。 相似文献
2.
为研究氨和空气暴露对大鳞副泥鳅血浆应激指标的影响,实验设置空气暴露组、氨暴露组和对照组3个组,将大鳞副泥鳅(Paramisgurnus dabryanus)分别置于圆形塑料盆(空气暴露组)、10 L 30 mmol/L NH_4Cl溶液(氨暴露组)、10 L纯水(对照组),3个组的暴露时间均设置为0、12、24、 48、72及96 h,每个暴露时间点均设置三个平行组,每个平行各装4尾。每个暴露时间点结束时,尾静脉取血测定血液生理指标。结果显示:空气暴露前24 h和氨暴露前12 h,大鳞副泥鳅血浆皮质醇含量均显著增加,而随后则显著下降。氨和空气暴露后,大鳞副泥鳅血糖含量均显著上升。空气暴露大鳞副泥鳅48 h内,其血浆乳酸含量的变化并不显著,而随后则显著上升。氨暴露条件下,大鳞副泥鳅血浆乳酸含量迅速上升,并在暴露12 h时达到最大值;随后迅速降至对照组水平。结果表明,氨和空气暴露可通过提高血浆皮质醇、血糖和乳酸含量以引起大鳞副泥鳅第一和第二阶段应激反应。血浆中皮质醇含量在氨和空气暴露一段时间后显著降低,在氨暴露72 h后降至对照水平,说明大鳞副泥鳅拥有某些特殊的氨耐受策略以应对体内外氨应激。 相似文献
3.
高碳酸盐碱胁迫对尼罗罗非鱼氨代谢基因表达变化的影响 总被引：1，自引：0，他引：1
为了解尼罗罗非鱼(Oreochromis niloticus)在碱环境适应过程中氨代谢调节途径,本研究选取了5个氨代谢相关酶:谷氨酰胺合成酶(glutamine synthetase,GS)、碳酸酐酶5A(carbonic anhydrase 5A,CA-5A)、谷氨酰胺酶(glutaminase 2,GLS2)、氨甲酰磷酸合成酶(carbamyl phosphate synthetase 1,CPS1)、氨转运蛋白(ammonium transporter Rh type C-2 like,Rhcgl2),研究了急性碳酸盐碱度胁迫条件下,尼罗罗非鱼血氨浓度变化、氨代谢相关酶基因表达水平及其酶活性变化。结果表明,随碳酸盐碱胁迫浓度升高,尼罗罗非鱼血氨浓度上升,随时间推移呈先上升后下降的变化趋势,在胁迫后12 h达到峰值。氨代谢相关基因在不同碱度下、不同组织中均有不同程度的上调表达,随着胁迫时间推移呈先上升后下降的变化趋势,胁迫后12~24 h各基因表达水平显著升高,随后逐渐恢复到稳定水平;氨代谢相关基因具有一定的组织表达差异:氨转运蛋白基因(Rhcgl2)主要在鳃中表达,碳酸酐酶5A基因(CA-5A)、谷氨酰胺合成酶基因(GS)、氨甲酰磷酸合成酶基因(CPS1)主要在肝中表达,谷氨酰胺酶基因(GLS2)主要在肾和鳃中表达。碳酸酐酶和谷氨酰胺合成酶活性随胁迫碱度的升高而上升,碳酸酐酶、谷氨酰胺合成酶活性变化分别在鳃、肝中最为显著。研究结果表明,碳酸盐碱度胁迫会引起尼罗罗非鱼血氨水平升高,随着时间推移血氨水平下降,推测鳃、肝、肾中不同氨代谢基因共同参与调节氨代谢,在鳃中通过直接排氨,在肝中通过合成谷氨酰胺、尿素途径,共同调节降低血氨水平。 相似文献
4.
为研究盐度对大鳞副泥鳅（Paramisgurnusdabryanus）Na+-K+-ATP酶（NKA）、抗氧化酶活性及组织结构的影响,试验设置4、8、12共3个盐度组和一个淡水组（对照）,以全长（17.60±0.69）cm,体质量（35.51±5.30）g的大鳞副泥鳅进行14 d胁迫试验。结果表明：盐度升高使鳃Na+-K+-ATP酶活力上升,第7 d 时3个试验组Na+-K+-ATP酶活性均达到峰值且盐度8和12组显著高于淡水组（P<0.05）。肝脏SOD和CAT活性均表现为先上升后下降的趋势,且分别于胁迫12 h和2 d时达到最大值;3个盐度组的GSH-PX酶活性在6 h和12 h均有所升高,且盐度12组显著高于淡水组（P<0.05）。盐度4、8和12组肝脏MDA含量分别在第1 d和7 d达到最大值且显著高于淡水组（P<0.05）。组织切片结果显示,盐度12组的鳃小片变窄,鳃小片间距变大,泌氯细胞数量增多;肝细胞空泡化严重,血窦扩张范围增大,并出现细胞轮廓模糊、细胞核偏移、细胞核溶解。上述结果表明,盐度胁迫对大鳞副泥鳅的Na+-K+-ATP酶、抗氧化酶活性具有显著的诱导作用,并对其鳃和肝组织造成损伤。 相似文献
5.
为了解罗非鱼在碱水环境适应过程中的氨代谢机制,将尼罗罗非鱼(Oreochromis niloticus)放在(2、4、6 g/L)碳酸盐(Na HCO3)碱水环境中进行急性胁迫。检测碱胁迫72 h内的血氨浓度,肝、肾、鳃组织及水体、尿液、血液尿素浓度变化,肝、脑、鳃谷氨酰胺(Gln)浓度,肝、脑谷氨酰胺合成酶(GS)活性,肝氨甲酰磷酸合成酶(CPS)活性,不同组织中GS、CPS、谷氨酰胺酶(GLS)的基因表达变化。结果显示:急性胁迫下尼罗罗非鱼血氨浓度上升,于12 h到达峰值。随着血氨升高,各组织中的尿素浓度0~6 h快速升高,CPS活性0~2 h快速升高,基因相对表达量0~24 h升高,表明尿素代谢途径0-6 h内启动。肝谷氨酰胺浓度0~6 h快速升高到达峰值,肝GS活性0~6 h和12~24 h快速升高,组织中GS、GLS基因相对表达量在0~24 h升高,表明谷氨酰胺代谢途径0~6 h内启动。结果表明,在碱胁迫条件下,尼罗罗非鱼在胁迫早期同时启动尿素代谢途径与谷氨酰胺代谢途径共同参与调节血氨浓度。 相似文献
6.
为了阐明肠道气呼吸对泥鳅的生理作用,本研究通过抑制大鳞副泥鳅肠道气呼吸,探究其主要呼吸器官的组织病理变化。结果显示,被抑制肠道气呼吸的大鳞副泥鳅通常在1周左右死亡。当被抑制肠道气呼吸的大鳞副泥鳅出现垂死时,采集对照组和实验组的鳃、皮肤、前肠、中肠、后肠以及直肠进行苏木素—伊红(H.E)染色、阿利新蓝—高碘酸雪夫氏(AB-PAS)染色组织切片观察和扫描电镜观察,主要的病理变化:①H.E染色结果显示实验组大鳞副泥鳅鳃丝末端充血,背部皮肤表皮层的毛细血管收缩并减少,且真皮层细胞呈畸形,前肠黏膜褶膨大,后肠浆膜层有血红细胞渗出,后肠、直肠结缔组织显著增厚;②AB-PAS染色结果显示,实验组大鳞副泥鳅鳃、背部皮肤、后肠、直肠组织中嗜酸性空泡细胞均增多,前肠和中肠固有层酸性黏蛋白含量增多,黏膜下层中性黏蛋白含量减少;③扫描电镜结果显示,实验组大鳞副泥鳅鳃丝鳃小片表面皱缩,表皮受损脱落,背部皮肤表面分泌孔增加,中肠内腔表面突起增多,后肠和直肠絮状颗粒增多。研究表明,抑制大鳞副泥鳅肠道气呼吸会引发其主要呼吸器官上皮组织出现黏液细胞增多、血红细胞溢出等病理变化,甚至导致机体死亡,由此可知,肠道气呼吸行为是大鳞副泥鳅的必要生理活动。本研究将为大鳞副泥鳅的健康养殖及幼苗培育提供新的参考。 相似文献
7.
为了解十二烷基苯磺酸钠(SDBS)对大鳞副泥鳅(Paramisgurnus dabryanus)胚胎发育及幼鱼性腺发育的影响,将受精卵随机分成7组,分别置于0、0.1、0.3、0.5、1.0、2.5、5.0 mg/L SDBS溶液中充氧孵化,统计培育周期、孵化周期、孵化率和畸形率。选取均重为3 g左右健康的大鳞副泥鳅210尾,随机分成7组,分别置于0、0.1、0.3、0.5、1.0、2.5、5.0 mg/L SDBS溶液中饲养60 d,统计大鳞副泥鳅的死亡情况,取性腺制作组织切片,观察SDBS对大鳞副泥鳅幼鱼性腺发育的影响。结果显示:SDBS浓度≤1.0 mg/L时,对大鳞副泥鳅受精卵培育周期、孵化周期、孵化率和鳅苗畸形率无显著影响,SDBS浓度≥2.5 mg/L时,培育周期与孵化周期显著延长,孵化率显著下降,鳅苗畸形率显著上升。大鳞副泥鳅的死亡率随SDBS浓度的升高明显上升,SDBS浓度≥0.1 mg/L时显著抑制精巢发育。 相似文献
8.
9.
三种鳅科鱼对NaCl盐度和NaHCO3碱度的耐受能力 总被引：2，自引：0，他引：2
以鳅科的黑龙江泥鳅(Misgurnus mohoity Dybowsky)、大鳞副泥鳅(Paramisgurnus dabryanus Sauvage)、达里湖高原鳅(Triplophysa dalaica)为实验材料,采用单因子静态急性毒性实验法和均匀正交设计法对其盐碱耐受能力进行研究。实验结果表明,黑龙江泥鳅、大鳞副泥鳅、达里湖高原鳅的24 h和96 h的氯化钠(Na Cl)盐度半致死浓度(LC50)分别为15.64 g/L和13.58 g/L、15.43 g/L和14.18 g/L、14.00 g/L和11.57 g/L,安全浓度(SC)分别为4.12 g/L、4.03 g/L、3.74 g/L,盐度耐受能力顺序为:黑龙江泥鳅大鳞副泥鳅达里湖高原鳅。黑龙江泥鳅、大鳞副泥鳅、达里湖高原鳅的24 h和96 h碳酸氢钠(NaHCO_3)碱度半致死浓度(LC50)分别为117.1 mmol/L和72.62 mmol/L、128.4 mmol/L和88.83 mmol/L、155.2 mmol/L和120.0 mmol/L,安全浓度分别为18.77 mmol/L、23.66 mmol/L、36.30 mmol/L,碱度耐受能力顺序为:达里湖高原鳅大鳞副泥鳅黑龙江泥鳅。盐碱交互作用对黑龙江泥鳅、大鳞副泥鳅均表现为协同作用,协同系数0~48 h依次增高,以后逐渐减小;而对达里湖高原鳅在0~48 h内表现为协同作用,在48~96 h时表现为拮抗作用,拮抗系数随着暴露时间的延长而增大。对比分析可知,3种鳅科鱼的盐碱耐受能力比大多数淡水鱼高,可作为盐碱水域的增养殖鱼类;而达里湖高原鳅在耐碱方面表现更突出,可以作为高碳酸盐型盐碱水的增养殖鱼类。 相似文献
10.
慢性氨氮暴露诱发黄颡鱼幼鱼谷氨酰胺积累、氧化损伤及免疫抑制的研究 总被引：2，自引：2，他引：0
为了研究慢性氨氮胁迫对黄颡鱼幼鱼生长性能、大脑谷氨酰胺积累、肝脏抗氧化酶活性、非特异性免疫应答及抗嗜水气单胞菌感染能力的影响,实验挑选初始体质量为(1.94±0.05)g的健康黄颡鱼幼鱼180尾,开展为期56 d的慢性氨氮胁迫实验.结果表明,实验鱼的终末体质量、增重及饲料效率,氨氮组与对照组无显著性差异,但肝体比氨氮组显著高于对照组;氨氮组实验鱼大脑中氨氮和谷氨酰胺含量显著高于对照组,但谷氨酸含量各组间无显著性差异;氨氮组实验鱼肝脏中超氧化物歧化酶、过氧化物酶及谷胱甘肽过氧化物酶活性显著低于对照组,但硫代巴比妥酸反应物含量氨氮组显著高于对照组;氨氮组实验鱼肝脏中溶菌酶活性、头肾巨噬细胞吞噬指数和呼吸爆发显著低于对照组;感染嗜水气单胞菌14d后,氨氮组和对照组实验鱼累计死亡率无显著性差异.研究表明,黄颡鱼幼鱼遭受亚致死浓度的慢性氨氮胁迫,能够导致大脑中谷氨酰胺含量升高;氨氮组黄颡鱼肝脏中硫代巴比妥酸反应物的过度积累表明,应激产生的大量自由基并不能被机体自身的抗氧化酶体系完全清除;亚致死浓度的慢性氨氮胁迫会对黄颡鱼幼鱼的免疫应答体系造成抑制. 相似文献
11.
Two dietary formulas containing 0% (D0 group) and 33% (D33 group) Ampithoe sp. meal were fed to Litopenaeus vannamei for 42 days, and then, an ammonia stress test was performed to explore the mechanism by which dietary Ampithoe sp. meal supplementation improves the ammonia tolerance of shrimp. The changes in key enzyme activities and biochemical substances involved in glutamine and urea synthesis in shrimp under ammonia stress were investigated. The cumulative mortality in the D0 group and D33 group was 62.22% and 44.44% respectively. With the prolongation of ammonia exposure, the ammonia concentration in the haemolymph of both groups increased, but that of the D33 group was significantly lower than that of the D0 group. The glutamate dehydrogenase (GDH) activity, glutamine concentration and urea‐N concentration in the haemolymph of the D33 group were significantly higher than those of the D0 group. In the gills of the D33 group, the glutamine concentration, arginase (ARG) activity and urea‐N concentration were significantly higher than those of the D0 group. In the hepatopancreas of the D33 group, the glutamine synthetase (GS) activity, glutamine concentration and urea‐N concentration were significantly higher than those of the D0 group. In the muscle of the D33 group, the GDH activity, GS activity, glutamine concentration and ARG activity were significantly higher than those of the D0 group. Consequently, our results indicated that dietary Ampithoe sp. meal supplementation could enhance glutamine and urea synthesis, thereby reducing ammonia accumulation in organisms, resulting in the improvement of ammonia tolerance in L. vannamei. 相似文献
12.
Xiao Fang Lai Huan Gao Jie Kong Qing Yin Wang Wei Ji Wang Xian Hong Meng 《Aquaculture International》2011,19(5):873-889
Glutamine synthetase (GS) is considered to be one of the oldest existing functioning genes in evolution and plays a key role
in two major biochemical pathways: in liver GS catalyzes ammonia detoxification, whereas in neural tissues it also functions
in recycling of the neurotransmitter glutamate. In this study, a cytosolic glutamine synthetase was cloned and characterized
from the Chinese Shrimp Fenneropenaeus chinensis, and named as FcGS. The results indicated that the full-length DNA of 1,756 bp had an open reading frame without intron,
which encoded a polypeptide of 366 amino acids with several conserved active site residues. The calculated molecular mass
of mature protein was 40.7 kDa and theoretical pI was 6.47. A phylogenetic analysis of GS sequences showed that FcGS clustered
with the invertebrate group as expected. qRT-PCR analysis indicated that FcGS was expressed in intestines, hepatopancreas,
muscles and gills, and its profile was up-regulated post-WSSV challenge in hepatopancreas and gills. Our results suggested
that FcGS might participate in the regulation of shrimp immune response toward WSSV invasion. These data would be helpful
to better understand the WSSV resistance mechanism of farming shrimps. 相似文献
13.
14.
Detoxification Pathways in Response to Environmental Ammonia Exposure of the Cuttlefish,Sepia pharaonis: Glutamine and Urea Formation 
下载免费PDF全文
下载免费PDF全文 Rui‐Bing Peng Ke‐Xin Le Peng‐Shuai Wang Yuan Wang Qing‐Xi Han Xia‐Min Jiang 《Journal of the World Aquaculture Society》2017,48(2):342-352
To investigate the ammonia detoxification pathways of the cuttlefish, Sepia pharaonis, the effects of environmental ammonia nitrogen exposure (control, 1, 3, and 6 mg/L) on nitrogen metabolism were quantified in the hemolymph, liver, and gills. The levels of glutamine synthetase, glutamate dehydrogenase, and arginase activities and ammonia, glutamine, and urea concentrations in the hemolymph, liver, and gills significantly increased upon exposure to 3 and 6 mg/L ammonia nitrogen and exhibited a dose‐dependent relationship with the ammonia exposure concentration. These results suggest two main pathways of metabolic ammonia detoxification in S. pharaonis exposed to ammonia in this study: (1) conversion of ammonia to urea, which is stored temporarily or excreted, via the ornithine‐urea cycle and (2) conversion of ammonia to glutamine, which can be stored in the body or used for other anabolic processes. 相似文献
15.
To evaluate if the addition of glutamine (Gln) precursors could enhance the utilization rate of plant protein on molecular level, the expressions of glutamine synthetase (GS) gene were analysed under supplementation of α‐ketoglutaric acid (AKG), ornithine‐α‐ketoglutaric acid (OKG), glutamic acid (Glu), and Gln. The relative quantification of GS gene expression in the plant meal (PM) group was significantly lower than the fish meal (FM) group. All the four additives increased the GS gene expression. The additive that most significantly increased the GS gene expression, Gln concentration and GS activity was glutamic acid. Supplementation of AKG in plant meal can improve the GS activity and Gln concentration. Effect of OKG on the activity of GS was not significant. The GS expression was up‐regulated by Gln, but had no significant effects on the Gln concentration and GS activity. In conclusion, substitution of plant protein for animal protein reduced the GS gene expression, and the supplementation of Gln precursors was capable of promoting the expression of GS gene in common carp. 相似文献
16.
Current intensive fish farming usually causes high environmental ammonia (HEA) in ponds that is toxic to fish. α‐Ketoglutarate (α‐KG) can be rapidly transaminated to glutamic acid and further aminated to glutamine. Therefore, we hypothesized that dietary α‐KG supplementation would alleviate HEA toxicity to fish. To test the hypothesis, 270 healthy grass carp (Ctenopharyngodon idella) juveniles were randomly assigned to control, HEA (18.37 mg/L ammonia) and HEA + α‐KG (0.75% of α‐KG) groups. Ammonia and free amino acid content in plasma and brain, liver glutamic pyruvic transaminase and glutamic oxaloacetic transaminase activity, and urea and glycogen content were measured on the first, seventh and 42nd days. Our results showed short‐term HEA exposure (1 day) led to a significant ammonia accumulation in the brain and plasma and significantly decreased glutamic and aspartic acid content in the brain and increased glutamine content in the brain and plasma. The long‐term HEA exposure (42 days) caused significant reductions in glycine and arginine content in the brain tissue. In most cases, dietary α‐KG supplementation alleviated the fluctuations in FAA content in the brain and plasma. Our results suggested dietary α‐KG alleviated HEA toxicity to grass carp. 相似文献