2种典型碳纳米管低浓度暴露诱发锦鲫组织损伤与肝脏氧化损伤效应研究

Tissue Damage and Liver Oxidative Damage of Goldfish(Carassius Auratus)Induced by Two Typical Low Concentration Carbon Nanotubes Exposure

采用半静态染毒方法,研究了单壁碳纳米管(SWCNT)和羟基化多壁碳纳米管(MCWNT-OH)对锦鲫抗氧化防御系统的影响。结果表明,锦鲫经28 d不同质量浓度的SWCNT和MWCNT-OH(0,10,100和1000μg/L)暴露后,暴露组14 d鳃组织切片检查发现出现鳃动脉瘤、鳃细胞水肿、畸形生长等病理症状;然而在2种碳纳米管低浓度暴露下,锦鲫的肝脏切片没有观察到损伤,高浓度时肝脏有轻微空泡损伤。暴露期间锦鲫没有死亡,随着暴露天数的增加,2种碳纳米管都能对SOD和CAT酶产生抑制作用,高浓度组抑制明显,肝脏抗氧化系统受到损伤。指出,虽然碳纳米管的毒性较低,但其长期暴露对鱼类的影响仍需进一步关注。

The impacts of SWCNT and MWCNT-OH on the antioxidant defense system of juvenile goldfish(Carassius auratus)were studied by semi-static exposure method.SWCNT and MWCNT-OH were found to induce histopathological and oxidative damages in liver.The results showed that the antioxidant enzymes SOD and CAT activity were inhibited significantly in the liver of goldfish exposed to 10,100 and 1000μg/L individually for 28 d.Individual exposure to SWCNT or MWCNT-OH at 14 d resulted in histopathological gill changes as follows:aneurisms,oedema in the secondary lamellae and hyperplasia in the primary lamellae.SWCNT and MWCNT-OH exposure was also found to induce necrosis and vacuolization in liver at the high dose of 1000μg/L.However,no changes were observed in liver at the low SWCNT or MWCNT-OH exposure level(dose of 10μg/L)compared to control.No lethal effects were observed during the test.With the increase of exposure days,two carbon nanotubes could inhibit SOD and CAT enzyme,and the inhibition was obvious in the group with high concentration,and the antioxidant system of the liver was damaged.The results indicated that the long term impacts of carbon nanotubes to fish need to be further investigated.