Effects of the toxic dinoflagellate Alexandrium tamarense on MDA,SOD and GST in hepatopancreas and gill of Fenneropenaeus chinensis

This study probes into effects of the toxic dinoflagellate Alexandrium tamarense(ATHK),a producer of paralytic shellfish poison,on antioxidant system of Chinese shrimp Fenneropenaeus chinensis,an important mariculture species in China.The shrimp were intramuscularly injected the crude toxin extracted from A.tamarense cells.The dose injection was carried out only one time during the experiment,using extracted solution from 1.4×103 algae cells.Superoxide dismutase(SOD)activity,glutathione-S-transferase(GST)activity and malondialdehyde(MDA)content were analyzed in hepatopancreas and gill at 1,3,6,12,24 and 48 h after stress.SOD activity and GST activity in hepatopancreas and gill increased within 6 h.However,they were inhibited in gill at 12 h and 48 h after stress.MDA content in hepatopancreas had no significant change except at 1 h after stress,but increased in gill with time prolonging.The results indicated that the crude toxin extracted from A.tamarense cells could cause lipid peroxidation in gill of F.chinensis by induction of MDA increase and SOD and GST inactivation.