Antioxidant effects and ATPase activity changes in hepatopancreas of mud crab Scylla serrata under low temperature acclimation

Mud crab,Scylla serrata,is a commercial species,which is eurytherm,living in estuary or seacoast.Because of fluctuating changes of environment temperature,the corresponding adaptation strategy will be used by S.serrata.Studies on physiology and biochemistry regulation in changes of environment temperature are important for the species culture and management. However,few papers on antioxidant effects and ATPase activity changes in S.serrata were published.This research was carried out to explore biochemistry adaptation mechanism in S.serrata from antioxidant defense and ATPase activity,and supply reference data for fishery management.S.serrata in this experiment were juvenile crabs,which were from special fishery for national 863 program.The individuals were cultured in 2 L containers respectively in a lighted-culture tank.After adaptation for 1 week,the crabs were divided randomly into four groups,and acclimated for 3 weeks after temperature decreasing to low temperature predefining in 1?℃/12?h respectively,then the samples were prepared and enzyme activity was determined.In this study,biochemistry methods were adopted to determine the activity of antioxidant enzymes(SOD,CAT and GPX) and the content of MDA,as well as the activity of Na~(+),K~(+)-ATPase,Mg~(2+)-ATPase,Ca~(2+)-ATPase and Ca~(2+),Mg~(2+)-ATPase in hepatopancreas of the juvenile of mud crab,Scylla serrata,under low temperature acclimation.The results showed that the activity of antioxidant enzymes(SOD,CAT and GPX) in hepatopancreas decreased gradually with decrease of acclimation temperature.However,the changes of MDA content were just contrary to that of the antioxidant enzyme activity.Activity changes of Na~(+),K~(+)-ATPase,Mg~(2+)-ATPase and Ca~(2+),Mg~(2+)-ATPase in hepatopancreas increased gradually with decrease of acclimation temperature;Ca~(2+)-ATPase activity did not show significant changes,but still increased in low temperature acclimation.The decrease of antioxidant enzyme activity indicated that physiological metabolism fell and enzyme activity decreased in organism under low temperature,thus MDA was accumulated in cells.Increase of ATPase activity in hepatopancreas under low temperature acclimation showed that there were obvious compensation effects of temperature in S.serrata,but various types of ATPase were different in activity changes.