A Study on Superoxide Dismutase from various Tissue of the Tricarboxylic acid cycle blocked Rat

Tricarboxylic acid회로를 차단한 흰쥐의 조직에서 Superoxide Dismutase에 관한 연구

This study was carried out to observe the formation of superoxide radicals and the changes in the activities of superoxide dismutase (EC.1.15.1.1.) from the various organs of a rat which was blocked tricarboxylic acid cycle. In order to block the tricarboxylic acid cycle, the beta-fluoroethylacetate was injected into peritoneal cavity of rat and removed the various tissues from the rat at internals of an hour. By tissue extracts being prepared by the method of Weigiger and Fridovich the activities of superoxide dismutase, aconitase, and contents of bliid glucose, citrates, and wuperoxide radicals were determined. The experimental results are summarized as follows: Accumulation of citrates if increased within three hours after treatment in the all tested tissues, especially, in the geart and spleen they are higher than one of other tissues as 12 and 20 times of control. The activities of aconitase are ingibited to 30-35% on an hour after beta-fluoroethylacetate treatment comparing with that of control rat. The content of blood glucose is increased to 1.6 fold of normal value after 5 hours of treatment. In all tested tissues, superoxide radicals are formed in the heart as 0.26 micromoles per gram tissue between one and three hours after treatment. The activities of total superoxide dismutase are increased between one and three hours after treatment in the all tested tissues and one of these enzymes in heart is highest. The activities of superoxide dismutase containing Mn are also increased with an increase of total superoxide dismutase activities.

$\beta$-fluoroethylacetate를 흰쥐의 복강에 투여하여 krebs cycle이 blocking된 것을 확인하고 이보 인해 각 조직 에서 생성되는 superoxide radical과 SOD의 할성도 변화를 관찰하였다. $\beta$-fluoroethylacetate을 투여한지 1- 3 시간 사이에 모든 장기에서 citrate의 축적농도가 가장 높았으며, 특히 heart외 spleen에서 12배 빛 20배로 가장 높았고, aconltase의 환성도는 한시간 후에 30-35%까지 억제되었고 시간의 경과에 따라 큰 변화는 없었다. 그리고 혈중 glucose의 함량은 계속증가되어 5 시간 후에 612mg/dl로 정상에 비해 1.6배 증가되었다. $\beta$-fluoroe thylacetate을 투여하고 1-2시간 후에 모든 장기에서 superoxide radical이 생성되었고 heart에서는 O. 26$\mu$mole/g호 가장 높았고, SOD의 총활성도는 1-3시간후에 활성이 가장 높았으며, heart에 있는 이 효소가 한 시간후 에 약 4 배로 가장 많이 증가되었다. Mn-SOD는 한시간 후에 모든 조직 에서 증가되였고 Kidney 가 가장 높은 활성도의 변화를 보였다. 이상의 결과로 흰쥐에서 Krebs cycle 이 차단되면 거의 모든 장기에서 superoxide radioal이 생성되며 Cu, Zn 및 Mn- SOD의 활성도가 모두 증가되고 특히 heart에시 가장 큰 변화를 보임을 알 수 있었다.