盐度升高对中华绒螯蟹几种非特异性免疫因子的影响

采用逐步增盐法, 结合生物酶学测定, 研究了从淡水升高盐度到 7、14、21、28和35对二秋龄雌、雄中华绒螯蟹血清总蛋白、氧合血蓝蛋白含量及碱性磷酸酶(AKP)、超氧化物歧化酶(SOD)、酚氧化酶(PO)活力的影响。结果显示, 随着盐度的升高, 中华绒螯蟹的血清总蛋白、氧合血蓝蛋白含量逐渐降低; AKP活性先略升高, 而后逐渐降低; 与雄蟹的PO活力逐渐降低相比, 雌蟹的PO活力先降低, 当盐度高于21后维持稳定水平; SOD活性先略降低, 盐度高于21被激活。除SOD外, 雌蟹血清各测定指标均显著高于雄蟹(P<0.05)。研究结果表明, 盐度接近或超过28将显著影响中华绒螯蟹3种免疫酶的活性及总蛋白和氧合血蓝蛋白的含量, 进而影响其免疫防御能力。

Changes in non-specific immune parameters of mature Chinese mitten crab (Eriocheir sinensis) in response to elevated salinities

Mature Chinese mitten crabs, Eriocheir sinensis, are exposed to brackish water or coastal waters as an obligatory part during adult reproductive migration. In this study, we investigated the changes in serum total protein and oxyhemocyanin contents, alkaline phosphatase (AKP), superoxide dismutase (SOD) and phenoloxidase (PO) activities in both mature male and female E. when in freshwater and after step-wise acclimation to the following salinities: 7, 14, 21, 28, 35. Increasing salinities caused a gradual decrease in serum total protein and oxyhemocyanin contents. Serum AKP activity was elevated slightly at 7, thereafter it dropped slowly by the end of experiment. Serum SOD activity showed a slight decrease after increase of salinity until 21, it was activated above 21. Serum PO activity decreased gradually with the increase of salinity in males; however, it maintained a stable level above 21 in females. All tested parameters in serum except for SOD were significantly higher in females than those in males. It is suggested that elevated salinity induced a decrease in serum total protein and oxyhemocyanin contents. Serum immune enzyme activities in mature E. sinensis will be affected when the salinity was near to or above 28, which could exert a negative effect on reproduction. Further studies are needed to understand the biochemical adaptation of mature E. sinensis, during their reproductive migration acclimation to elevated salinities. Sex differences should not be ignored.