摘要
在水温23-28℃下,将体质量80-100g的吉富罗非鱼饲养在模拟养殖系统中,投喂10g/kg的三聚氰胺饲料10d,然后再喂养不含三聚氰胺的饲料10d,考察了不同时间下吉富罗非鱼肝脏中过氧化氢酶、超氧化物歧化酶、7-乙氧基—异酚噁唑酮—脱乙基酶和谷胱甘肽-S-转移酶活性的变化。结果显示,在饲料暴露的第1d,显著诱导了吉富罗非鱼肝脏中过氧化氢酶、超氧化物歧化酶、7-乙氧基—异酚噁唑酮—脱乙基酶和谷胱甘肽-S-转移酶的活性,诱导率分别为104.2%、15.6%、27.7%和75.8%。随着暴露时间的延长,4种酶的活性均有所下降,在暴露第6d、10d、10d和第6d开始被抑制,抑制率分别为52.2%、17.4%、5.9%和9.0%。在停止投喂含三聚氰胺的饲料后,再次诱导过氧化氢酶、7-乙氧基—异酚噁唑酮—脱乙基酶和谷胱甘肽-S-转移酶的活性,但超氧化物歧化酶的活性依然受抑制。试验结束时4种酶的活性均恢复到暴露初期的水平,与对照组差异不显著。在饲料三聚氰胺暴露的10d中,吉富罗非鱼肝脏中过氧化氢酶、超氧化物歧化酶、7-乙氧基—异酚噁唑酮—脱乙基酶和谷胱甘肽-S-转移酶活性的活性均呈现出＂诱导—抑制＂的趋势,在停止暴露10d后,上升到正常水平。饲料中的三聚氰胺扰乱了吉富罗非鱼肝脏酶系的正常功能,停止暴露后可逐步恢复正常。
Nile tilapia Oreochromis niloticus with body weight of 80—100g were cultivated in a simulated aquatic micro-system and fed diets containing melamine at a dose of 10g/kg for 10 days,and then fed basal feed for 10 days at 23—28 ℃,to evaluate effects of dietary melamine on activities of catalase（CAT）,superoxide dismutase（SOD）,7-ethoxyresorufin-O-deethylase（EROD）and glutathione S-transferase（GST）in tilapia liver at various experimental times.These enzyme activities were shown to be significantly induced,with inducement rates of 104.2%in CAT,15.6%in SOD,27.7%in EROD and 75.8%in GST on the first day,and then to be decreased with the elapse of exposure time,inhibition by 52.2%for CAT at the 6th day,17.4%for SOD at the 10 th day,5.9%for EROD at the 10 th day and 9.0%for GST at the6 th day.The activities of CAT,EROD and GST were induced again in the fish fed the basal diet,but the activity of SOD was still inhibited.At the end of the test,the enzyme activities were resumed normal levels in the treated group,without significant differences compared with the control group.Generally,during the melamine exposure period,the activities of CAT,SOD,EROD and GST in the tilapia liver in the treated group followed a change tendency of inducement and then inhibition with the increase in exposure time.At the 10 th day without exposure of melamine,all these activities in the treated group were enhanced to normal levels.
出处
《水产科学》
CAS
CSCD
北大核心
2015年第2期77-82,共6页
Fisheries Science
基金
国家自然科学基金资助项目(41071315.)
