将水温分别由7.50℃、4.25℃和1.95℃骤降至冰点并保持24 h,期间测量光滑河蓝蛤(Potamocorbula laevis)闭壳肌中的超氧化物歧化酶(SOD)、过氧化氢酶(CAT)、溶菌酶(LZM)、酸性磷酸酶(ACP)和碱性磷酸酶(AKP)活性。根据生态免疫学理论,将每个酶活性分解为3个分量,即特定水温下酶活性基准值;水温骤降过程中温差引起应激响应的酶活性波动和低温环境引起冷应激响应的酶活性波动,根据3个响应特征分别给予合适的数学表达形式。再用3分量数学表达式之和作为整个响应的表达式来拟合各种酶活性随时间的变化过程。发现5种酶活性具有相同的变化规律,水温骤降过程中温差引起应激响应的酶活性波动早于低温环境引起冷应激响应的酶活性波动,并且波动的峰值也是前者高于后者。另外该方法可以弥补柱状图不能够表述完整过程的弱点。
The activity levels of superoxide dismutase (SOD) , catalase (CAT), lysozyme (LZM), acid phosphatase (ACP), and alkaline phosphatase (AKP) in the clam Potamocorbula laevis were measured, while the seawater tem- perature was rapidly decreased to freezing point from 7.50 ℃, 4.25 ℃, 1.95 ℃ and kept 24 h. The enzyme activity has been decomposed into the baseline value at different temperature levels, and the enzyme activity for stress re- sponse on temperature plummeting and sustained low temperature, which based on the theory of ecological immunolo- gy. Then, the decomposed enzyme activities were expressed using suitable mathematical expressions. The stress re- sponse course of enzyme activity with time was fitted using the expression superimposed by 3 components expression. It is found that there was same change trends among the five enzymes. The fluctuation that was leaded by temperature plummeting was occurred earlier than that was caused by sustained low temperature, and the peak value of fluctuation in the former was higher than that in the latter. The method can present full process to compensate for the imperfection of histogram and provide activity levels and appearance time of peak value.