蓖麻蚕滞育与过氧化氢代谢的关系

The Relationship Between Diapause and Hydrogen Peroxide Metabolism in Castor Silkworm,Attacus cynthia ricini B.

为了探讨蓖麻蚕滞育的机理，研究了蓖麻蚕蛹H2O2代谢的变化，并比较了在5℃冷藏滞育条件下的差异。结果表明，常温环境蓖麻蚕蛹期的H2O2含量呈减少趋势，第3～5天急速变化，超氧化物歧化酶（SOD）和过氧化氢酶（CAT）活性在第5天出现活性峰，故蛹期第3～5天是蓖麻蚕生理变化的一个敏感时期。第3天开始蛹滞育条件5℃冷藏，雄蛹在30d前后、雌蛹在80d左右H2O2含量出现快速改变；SOD和CAT活性一直呈下降趋势，但自30d开始CAT活性出现快速下降过程，5℃冷藏30d是蓖麻蚕蛹H2O2代谢的临界期生理时间，这与蚕蛹的30d冷藏阈值时间吻合。

In order to study the diapause＇s mechanism, the change of hydrogen peroxide metabolism in the pupae stage of castor silkworm and comparative difference between normal temperature and 5℃ cold storage were researched. The results showed that contents of hydrogen peroxide （H202） tend to decrease in the pu- pae stage in normal temperature, and change dramatically in 3 to 5 days old. Meanwhile, activities of superoxide dismutase （SOD） and catalase （CAT） come to the peak in 5 days old. So concerning the physiological change, 3 to 5 days old is a sensitive stage of castor silkworm. When the pupae are under 5℃ cold storage in the beginning of 3 days old, contents of H2O2 change rapidly in about 30 days old of male and 80 days old of female, and activities of SOD and CAT always fall off. But activities of CAT fall quickly from 30 days. So 30 days is physiologically a critical period of hydrogen peroxide metabolism under 5℃ cold storage and is consistent with the threshold value of cold storage of pupae.