【摘要】 过氧化氢（Ｈ_２Ｏ_２）是生物体内主要的活性氧来源之一。在超氧化物歧化酶（ＳＯＤ）、过氧化氢酶（ＣＡＴ）等的催化作用下，Ｈ_２Ｏ_２。被降解，释放出活性氧。所以，生物个体发育过程中体内Ｈ_２Ｏ_２、ＳＯＤ和ＣＡＴ含量的变化反映着Ｈ_２Ｏ_２的代谢水平。另外，家蚕是蚕卵滞育昆虫，实验设计考虑到了滞育前后可能会有的差别。取产后１０分钟内的卵为供试材料。采用即时浸酸法解除卵滞育。采用比色法和氧电极法测定并比较家蚕胚胎滞育形成与解除过程中过氧化氢的代谢。结果表明：（１）受精初期（０～４ｈ），Ｈ_２Ｏ_２含量在２．５ｈ时达到峰值（Ｆｉｇ．１），相应地ＳＯＤ活性处于较高水平，而ＣＡＴ活性处于最低水平（Ｆｉｇ．２）；（２）胚胎发育过程中（即时浸酸解除滞育），Ｈ_２Ｏ_２含量除１６８～２１６ｈ处于低水平外均显著高于滞育卵（Ｆｉｇ．３），ＳＯＤ活性分别在７２ｈ、１６８ｈ，形成小大两峰，后期显著高于滞育卵（Ｆｉｇ．４），而ＣＡＴ活性７２－１９２ｈ保持平稳，随后急剧上升，前期显著低于滞育卵，后期相反（Ｆｉｇ．５）；（３）滞育形成过程中Ｈ_２Ｏ_２水平变化平缓（Ｆｉｇ．６），ＳＯＤ活性前期剧烈变动，但后期保持平稳（Ｆｉｇ．７），ＣＡＴ活性逐步升更多还原

【Abstract】 Metabolism of hydrogen peroxide in the course of embryonic development ofsilkworm （variety Guang） was determined by using colorimetric analysis and oxygen electrodemethod. The results indicated that: 1) In the course of fertilization （0-4 h after egg laying）, thelevel of H₂O₂ content reached its peak value at 2.5 h of the developmental course and the activity ofsuperoxidase dismutase （SOD） was at higher level while the activity of catalase （CAT） at the lowestcorrespondingly; 2) The H₂O₂ content in embryo, in which the diapause of eggs was being relievedthrough treatment with hydrochloric acid on time in the course of embryonic development, wassignificantly higher than that of diapause eggs except the lower level showed in the embryo whenthe development of it went on for 168²16 h and the activity of SOD reached, lower and higher,tWo peaks in 72 and 168 h after egg-laying, respectively, and was significantly higher in late stagewhile the activity of CAT was shown with a stable level in the period of 72-192 h after egg-laying,and, after then, a rapid rising occurred in the embryo. The level of the CAT activity in embryowas shown significantly lower than that in diapause eggs in early period and higher in late stage ofegg development; 3) In the course of formation of diapause in eggs, the level of H₂O₂contentchanged smoothly and the activity of SOD changed vigorously in early period, and kept stable statelater; and the CAT activity increased gradually; while in the course of relief of diapause under ontime-treatment with hydrochloric acid, the level of H₂O₂ was significantly higher than that indiapause eggs and the SOD activity displayed a new peak value and significantly rose in later stage,while the activity of CAT in relieving embryo from diapause was signincantly lower than that indiapause eggs. Combining the results obtained in other researches with those from ours mentionedabove, we suggest that the metabolism of H₂O₂ might be of importance in the courses of formationand relief of diapause in silkworm eggs. Maybe the esterase A4 timer hypothesis and themicropylar barrier to oxygen hypothesis could be integrated for explanation of the course offormation and relief of diapause in silkworm eggs.更多还原