ICR순계 마우스에 electroconvulsive shock(ECS)을 가해 뇌조직에서 superoxide radical의 생성, $H_2O_2$의 양, superoxid edismutase(superoxide: superoxide oxidoreductase, EC 1.15.1.1)의 활성에 미치는 영향 등을 관찰하고, 주기적으로 반복하여 ECS를 가함으로써 superoxide dismutase(SOD)를 유발시켜 합성 및 분해속도상수를 구한 결과 다음과 같은 결론을 얻었다. 1. ECS를 받은 마우스의 뇌조직 균질액에서 superoxide radical의 생성이 대조군에 비해 유의한 차이가 있게 증가되었다(p<0.01). 2. ECS에 의해 마우스 뇌조직의 SOD 활성도는 긴장성 경련기에, $H_2O_2$의 양은 1분후에 가장 높은 증가를 나타내었으며 SOD 활성도와 $H_2O_2$양의 변화 양상은 비슷하였다. 3. 일련의 ECS로 세포질 SOD는 대조군의 약 1.6배로 전기자극 후 11일에 가장 높은 활성을 나타냈다($Kd=3.60{ imes}10^{-2}/hr$; Ks=6.01 units/hr/g tissue; $t_{1/2}=19;hrs$). Mitochondria의 SOD는 전기자극후 11일에 대조군의 약 2배로 가장 높은 활성을 나타내었다($Kd=1.53{ imes}10^{-2}/hr$; Ks=1.44 units/hr/g tissue; $t_{1/2}=45;hrs$). 4. 회복기에 세포질 효소의 속도상수는 Kd가 $1.91{ imes}10^{-2}/hr$, Ks가 2.01 units/hr/g tissue, 반감기는 36시간이었으며, mitochondria 효소의 Kd는 $3.08{ imes}10^{-2}/hr$, Ks는 1.42 units/hr/g tissue, 반감기는 23시간이었다.
In the present study, prolonged effects of the serial electroconvulsive shocks on the activity of superoxide dismutase (superoxide: superoxide oxidoreductase, EC 1.15.1.1): both cyanide-sensitive cytosolic enzyme and cyanide-resistant mitochondrial enzyme, were observed in the mouse brain. The rate constants for synthesis and degradation of these enzymes were determined. In addition, the changes in the superoxide radical production, the amount of hydrogen peroxide and the activity of superoxide dismutase were observed in the mouse brain which received single electroconvulsive shock. The results were summarized as follows: 1. Homogenates prepared from the brains of mice treated with single electroconvulsive shock showed considerably higher superoxide radical production when compared with those of the control mice. 2. By single electroconvulsive shock the generation of hydrogen peroxide increased at 1 minute after the electric stimulus; while the activity of superoxide dismutase increased at the time when tonic convulsion occurred. 3. By the serial electroconvulsive shocks the activity of cytosolic superoxide dismutase increased to approximately 1.6 times its control value ($Kd=3.60{ imes}10^{-2}/hr$; Ks=6.01 units/hr/g tissue; $t_{1/2}=19;hrs$); and the mitochondrial enzyme increased to approximately 2 times its control value ($Kd=1.53{ imes}10^{-2}/hr$; Ks=1.44 units/hr/g tissue; $t_{1/2}=45;hrs$). 4. The rate constants at recovery period were: $Kd=1.91{ imes}10^{-2}/hr$; Ks=2.01 units/hr/g tissue; $t_{1/2}=36;hrs$ for the cytosolic superoxide dismutase and $Kd=3.08{ imes}10^{-2}/hr$; Ks=1.42 units/hr/g tissue; $t_{1/2}=23;hrs$ for the mit ochondrial enzyme.
