백서 뇌 K+-dependent p-Nitrophenylphosphatase활성에 관한 연구

• 영문명: Studies on the K⁺-dependent p-Nitrophenylphosphatase activity of the rat brain
• 발행기관: 대한생리학회
• 저자명: 구진일(Koo, Jin-Il)
• 간행물 정보: 『대한생리학회지』제8권 제2호, 59~66쪽, 전체 8쪽
• 주제분류: 의약학 > 의학일반
• 파일형태: PDF
• 발행일자: 1974.12.31

영문 초록

In recent years much interesting information about the mechanism of the Na⁺-K⁺ activated ATPase has been obtained from investigation of the K⁺-activated phosphatase activity which appears to be catalysed by the same enzyme. Also several studies have indicated that a K⁺-activated p-nitrophenylphosphatase activity is intimately related to the ATPase activity. And then the exact relation of p-nitrophenylphosphatase activity to Na⁺-K⁺ ATPase activity is not known. The effects of some ions and drugs on the p-nitrophenylphosphatase activity of the rat brain were investigated and the results were summarized as follows. 1. The p-nitrophenylphosphatase was stimulated markedly by low concentrations of K⁺, while the activity was activated slightly in the presence of Na⁺ and oligomycin. 2. Addition of both ATP and Na⁺ caused a remarkable increase in the activity of the K⁺-dependent phosphatase at low concentrations of K⁺. 3. In the presence of Na⁺ and low concentrations of K⁺, oligomycin activated the p-nitrophenylphosphatase. 4. O1igomycin inhibited the stimulation of the enzyme activity caused by Na⁺+ATP. 5. Ouabain inhibited the K⁺-dependent p-nitrophenylphosphatase activity more in the presence of ATP and Na⁺ than in their absence. 6. Quinidine inhibited both Na⁺-K⁺ ATPase and p-nitrophenylphosphatase. These inhibitory effects of the drug were partially antagonized by increasing K⁺ concentrations. The sensitivity of the K⁺-dependent p-nitrophenylphosphatase to quinidine was greater than the that of Na⁺-K⁺ ATPase.