不同水温下重金属镉诱导金属硫蛋白在鲫鱼组织中的表达

以鲫鱼(Carassius auratus)为试验材料,研究了在一定环境条件下重金属镉的胁迫对鲫鱼不同组织中金属硫蛋白(MT)含量的影响.结果表明.平均体长为(15.32±0.63)cm、平均体重为(310.6±5.69)g的鲫鱼不同组织中的MT本底值存在着明显的差异(P<0.01),含量顺序为肝脏>肾脏;不同水温条件下鲫鱼相同组织中的MT本底值差异显著(P<0.01),鲫鱼肝脏中的MT本底值平均含量在水温(26.5±1)℃和(16.5±1)℃时分别为3.50和3.25μg·g~(-1);肾脏中的MT平均含量分别为3.20和2.72μg·g~(-1);不同水温下,经不同的暴露时间、不同暴露浓度的Cd~(2+)胁迫下MT在鲫鱼肝脏和肾脏中的表达趋势较为一致,都是旱先升高后稳定的状态,在试验后的6 h内的增加速率最大,MT的含量在12 h时达到峰值.鲫鱼的肝脏和肾脏组织在12 h内MT的增加量与Cd~(2+)的浓度呈较好的相关性,表现出一定的剂量一效应关系.表明水体中的Cd~(2+)可诱导鲫鱼组织中MT的合成与表达,且主要诱导时间在12 h之内.相同Cd~(2+)质量浓度胁迫下,水温的改变不影响Cd~(2+)胁迫MT在鲫鱼组织中的表达趋势,但影响MT表达的含量和速率,相同Cd~(2+)质量浓度下MT在鲫鱼组织中的表达含量和速率均随水温的升高而增加.

Metallothionein in Different Tissues of Carassius auratus Exposing to Cadmium Under Different Temperatures

This research investigated the impact of waterborne cadmium on the content of metallothionein (MT)in liver and kidney of Carassius auratus in experimental condition. The result indicated that there was a significant differences of the background MT value in Carassius auratus tissues( P<0.01). The MT concentration in liver was higher than that of kidney. The background MT average value in liver is 3.50 μg· g~(-1) and 3.25 μg·g~(-1) respectively under water temperature was(26.5±1 )℃ and( 16.5±1 )℃,in kidney was 3.20 μg·g~(-1) and 2.72 μg·g~(-1); The expression of MT in liver and kidney reached a peak at 12 h and then differently decreased at 24 to 48 h and kept stable, and the increasing rate was the highest in 6 h. The analysis relevant indicated there was a better positive correlation between the MT contents and the concentration of Cd~(2+) in 12 h. The change of water temperature cannot change the expression tendency of MT in Carassius auratus tissue, but influence the expression rate and contention of MT. The MT contents and expression rates in Carassius auratus tissue increased with the increasing of temperature at the same content of exposing to cadmiumion.