右旋糖酐铁和嗜水气单胞菌感染对泥鳅GSTs活力的影响

Influences of glutathione-S-transferase on mud loach challenged with bacteria Aeromonas hydrophila and iron dextran

以泥鳅为试验材料,利用嗜水气单胞菌和右旋糖酐铁作为诱导刺激物,以不同浓度嗜水气单胞菌菌液和右旋糖酐铁对泥鳅进行腹腔注射,研究病原细菌和金属离子对泥鳅GSTs酶活性的影响。在分别注射病原微生物后02,6,,101,62,44,0,50 h以及注射右旋糖酐铁后12,,3,4,5 d取泥鳅肝胰组织,测定其谷胱甘肽-S-转移酶(GSTs)的活力,并研究其变化规律。结果表明:不同浓度的嗜水气单胞菌对泥鳅GSTs均有诱导作用,2.1×109 cfu.mL-1浓度组对泥鳅GSTs的诱导作用最大,2.1×107和2.1×105 cfu.mL-1浓度组则相对来说诱导作用较小。各处理组GSTs活力在处理后一段时间内达到峰值后逐渐降低到正常水平,实验组的GSTs活力均显著高于对照组。不同浓度的右旋糖酐铁对GSTs的作用不同,低剂量组(10μg.g-1)对GSTs活性有显著性的诱导作用(P<0.05),且在第1天时诱导作用达到最大,随后逐渐降低到正常水平;中剂量组(25μg.g-1)和高剂量组(50μg.g-1)对GSTs活性有一定抑制作用,且在第4天时抑制作用达到最大,但随后逐渐增加而趋近于正常水平。

Mud loach is widly distributed in East-Asia.Previous reports showed that glutathione-S-transferase（GSTs） was one key element in the detoxication procedure of immune system.The aim of this study was to investigate the influences of different concentrations of Aeromonas hydrophila and iron dextran on glutathione-S-transferase in mud loach.The liver was extracted and homogenated to obtain the GSTs in different time after injection.The activities of GSTs were analyzed and the results showed that different concentrations of Aeromonas hydrophila induced the expression of GSTs in livers of loaches.The group treated with 2.1×109cfu·mL-1 had the strongest ability to induce the activity of GSTs.However,the group treated with 2.1×107 cfu·mL-1 and 2.1×105 cfu·mL-1 showed a smaller induction on activity of GSTs than 2.1×109 cfu·mL-1 group.The activity of GSTs reached the peak several hours after injection and then dropped to the normal level,and the GSTs activities of treatment groups were significantly higher than the control.After injection of iron dextran,we found that different concentrations of iron dextran showed different effects on GSTs activities.The GSTs activities was the highest when treated with 10 μg·g-1 iron dextran,and reached the peak at 1 d after injection and then dropped to the normal level during the following days.However,the GSTs activities was inhibited when treated with 25 μg·g-1 and 50 μg·g-1 iron dextran,which was the strongest at 4 d after injection with iron dextran and then increased to the normal level.