异戊二烯对刺参急性毒性及其抗氧化酶和免疫酶活性的影响

为研究有机污染物对海洋生物的毒性影响,选择海洋环境中典型的异戊二烯作为暴露污染物,研究其对体质量为(5.23±0.96)g刺参Apostichopus japonicus的急性毒性及其体腔液中超氧化物歧化酶(SOD)、过氧化氢酶(CAT)、酸性磷酸酶(ACP)和碱性磷酸酶(AKP)活性的影响,并在实验室条件下,采用静水式生物毒性试验法开展了急性毒性试验,以及96 h亚致死效应的毒性试验。结果表明:异戊二烯对刺参的24、48、72、96 h半致死质量浓度分别为83.00、78.09、72.93、69.77 mg/L,安全质量浓度为6.98 mg/L;亚致死试验中,CAT活性受到的影响最大,表现为受到抑制作用,存在良好的剂量-效应和时间-效应正相关性;96 h时,中、低浓度异戊二烯对SOD活性具有显著的诱导作用(P0.05),而高浓度异戊二烯对SOD活性具有极显著的抑制作用(P0.01);ACP和AKP活性受到的影响较小,但48 h时两种酶均受到极显著的诱导作用(P0.01),96 h时AKP活性受到显著的诱导作用(P0.05);随着异戊二烯质量浓度的增加和时间的延长,刺参体腔液中4种酶活性受到不同程度的影响,因此,异戊二烯胁迫对刺参体内产生自由基导致氧化胁迫效应,以及对消化、能量代谢系统的影响可能是其重要的致毒原因,刺参体腔液中4种酶的变化体现了异戊二烯的致毒机制。本研究结果可为异戊二烯对海洋生物的生态毒理学方面的研究提供参考依据。

Acute toxicity and effects of isoprene on activities of antioxidant and immune enzymes in sea cucumber Apostichopus japonicus

Acute toxicity of isoprene, a common toxic pollutant in marine environment, to sea cucumber Aposticho-pus japonicas with body weight of (5.23±0.96) g was studied in a laboratory by static bioassay and effects of iso-prene on activities of superoxide dismutase ( SOD) , catalase ( CAT) , acid phosphatase ( ACP ) and alkaline phos-phatase ( AKP ) were investigated in coelomic fluid of sea cucumber. The results showed that the median lethal con-centration (LC50) of isoprene to sea cucumber was 83.00 mg/L in 24 h, 78.09 mg/L in 48 h, 72.93 mg/L in 72 h, and 69.77 mg/L in 96 h, with safe concentration of 6.98 mg/L. In sublethal effect test, the activities of CAT were the most sensitive and inhibited in isoprene treatment groups, with good time-dose dependent effect, and the activities of SOD were induced in the medium and low concentration of isoprene treatment groups and inhibited very significantly in the high concentration treatment groups at 96 h ( P<0.01) . The activities of ACP and AKP were less sensitive to isoprene, and significantly induced at 48 h ( P<0.01) , and the activities of AKP were significantly in-duced at 96 h ( P<0.05) . The activities of four enzymes in the coelomic fluid of sea cucumber were affected by iso-prene with the increase in isoprene concentrations and time prolonged, indicating that the toxic mechanisms of iso-prene is involved in generated free radicals, oxidative stress and the effects on digestive and metabolic systems in sea cucumber. The findings may provide the reference on ecological toxicology of isoprene to marine organisms.