Effects of acute temperature and salinity stress on heat shock protein gene expression and antioxidant enzyme activity in Macrobrachium rosenbergii

【Objective】 To investigate the effects of acute temperature and salinity stress on the heat shock protein gene and antioxidant enzyme activity of Macrobrachium rosenbergii，which could provide reference basis for the healthy aquaculture of M. rosenbergii in actual production. 【Method】 Using two-factor test with different temperatures（20，24，28 and 32 ℃）and salinity（0.5‰，4.0‰，8.0‰ and 12.0‰），16 treatment groups in total，transferred M. rosenbergii from the initial temperature（24 ℃）and salinity（0.5‰）to the environment of each treatment group for acute stress. At 24 and 48 h of stress，the gill and hepatopancreas tissues of M. rosenbergii were taken for measurement of the expression level of heat shock proteins 70 gene（HSP70）and the activities of superoxide dismutase（SOD）and glutathione peroxidase （GPX）. 【Result】 At 24 h of stress，with the increase of salinity，the relative expression of HSP70 gene in gills and hepato‐ pancreas increased first and then decrease；at 0.5‰ and 4.0‰ salinity，the relative expression of HSP70 gene in gills and hepatopancreas of M. rosenbergii at 28 and 32 ℃ was higher than 24 ℃，moreover，the relative expression of HSP70 gene in hepatopancreas at 28 and 32 ℃ was significantly higher than 20 ℃（P<0.05，the same below）. After 48 h of stress，the relative expression of HSP70 gene at 8.0‰ and 4.0‰ salinity at 24 ℃ of gill and hepatopancreas tissues in M. rosenbergii was higher than 0.5‰ and 4.0‰ salinity. Under the same temperature at 24 h of stress，the activities of SOD and GPX in gill tissue of M. rosenbergii increased with the increase of salinity. When temperature was 24 ℃，SOD and GPX activities in hepatopancreas tissue had no significant changes with the increase of salinity（P>0.05），but had obvious changes at other temperatures. Under the same salinity，SOD activity in gill tissue and GPX activity in hepatopancreas tissue decreased first and then increased with the increase of temperature，GPX activity in gill tissue and SOD activity in hepatopancreas tissue increased as a whole. The results of two-factor ANOVA showed that temperature，salinity and their interaction had extremely significant effects on HSP70 gene expression and antioxidant enzyme（SOD and GPX）activity in gills and hepatopancreas of M. rosenbergii（P<0.01）. 【Conclusion】 Acute temperature and salinity stress can increase the relative expression of HSP70 gene in M. rosenbergii，and sudden rise of temperature can induce HSP70 gene expression more than sudden fall of temperature. Temperature and salinity can cause the change of antioxidant enzyme activity of M. rosenbergii，and the influence of temperature on antioxidant enzyme activity is greater than salinity. By regulating the relative expression of HSP70 gene，SOD activity and GPX activity，M. rosenbergii synergously regulated its physiological function to adapt to external salinity and temperature changes，and enhanced its tolerance to harsh environment.