镉对鲫鱼鳃和肝脏超氧化物歧化酶活性的影响

EXPERIMENT WITH EFFECT OF CADMIUM ON ACTIVITY OF SUPEROXIDE DISMUTASE IN GILL AND LIVER TISSUE OF CRUCIAN

使用浸浴法以 0 mg/ L、0 .73 mg/ L、1 .46 mg/ L、2 .95 mg/ L 4个镉 (Cd Cl2 · 2 .5H2 O)浓度为丰产鲫 (Carassiusauratus of Penze(♀ )× Cyprinusacutidorsalis(♂ ) )幼鱼染毒 ,测定了 1 4 4 h内鳃及肝组织中超氧化物歧化酶 (SOD)活性的变化。结果表明 ,低浓度组Cd曝露时 ,鲫鱼鳃和肝组织中 SOD活性的变化短时间内不明显 ,但随着处理时间的延长 ,Cd提高了鳃和肝组织中 SOD的活性 ,导致“毒物兴奋效应”。高浓度组 Cd曝露时均抑制了肝和鳃中的 SOD活性 ,其作用随着曝露时间的延长和浓度的升高而增强 ,SOD酶活性降低所造成的活性氧伤害是引起鲫幼鱼死亡的重要原因。肝组织中的 SOD酶活性和敏感性高于鳃 。

This paper presents an experiment the author has done with the crucian when it was exposed to cadmium to test the influence of the cadmium polluted sludge on the fish activities. With crucian exposed to cadmium (CdCl 2·2.5H 2O) with 0 mg/L, 0.73 mg/L, 1.46 mg/L, 2.95 mg/L for 6 days, the authors intend to determine the activities of superoxide dismutase (SOD) of gill and liver tissues in 144 h by means of improved pyrogallol autoxidation. The results of the experiment indicate that the activities of SOD in gill and liver haven't made any obvious change at low Cd concentrations in a short time. The activities of SOD, however, would increase with the exposure time going on, which may probably come about as a result of the 'Toxic excitement effect'. With the high concentration Cd inhibiting the activities of SOD in gill and liver, the inhibiting strength will increase with the prolonging of the exposure time and the concentration enhancing. Thus, it suggests that the harm caused by active oxygen due to the decrease of the activities of SOD is an important reason that leads to the mass death of crucian exposed to Cd. The experiment also indicates that the activities and sensitivities to Cd of SOD in liver are higher than those in gill, which may be associated with their physiological functions.