Ogawa E, Horii Y, Honda M, Takahashi R
Department of Pathology II, Azabu University, Kanagawa, Japan.
J Vet Med Sci. 1994 Oct;56(5):873-7. doi: 10.1292/jvms.56.873.
The methemoglobin formation and methemoglobin reduction in canine erythrocytes characterized by inherited high potassium (K+) and normal reduced glutathione concentrations (HK-low GSH cells) were compared with those in canine erythrocytes with inherited high K+ and high GSH concentrations (HK-high GSH cells) and normal canine erythrocytes with low K+ and low (= normal) GSH concentrations (LK-low GSH cells). The rate of methemoglobin formation induced by sodium nitrite (NaNO2) was in the order; LK-low GSH > HK-low GSH > HK-high GSH cells, and the difference among groups was significant at 7 and 15 min. Methemoglobin reduction in a medium containing glucose occurred rapidly in both HK-high GSH and HK-low GSH cells, and the rate of reduction was 1.7-fold higher than in LK-low GSH cells. Accumulation of pyruvate equivalent to the amount of methemoglobin reduced indicated that methemoglobin was predominantly reduced by NADH-methemoglobin reductase coupled to glycolysis. HK-low GSH cells showed an increased glycolytic rate and high pyruvate kinase activity similar to the levels in HK-high GSH cells. It is therefore evident that HK-low GSH cells offer greater protection against oxidation of hemoglobin to methemoglobin than LK-low GSH cells because of the increased glycolytic rate in HK-low GSH cells attributable to high pyruvate kinase activity in these cells.
将遗传性高钾（K +）和正常还原型谷胱甘肽浓度（HK - 低GSH细胞）的犬红细胞中的高铁血红蛋白形成和高铁血红蛋白还原，与遗传性高K +和高GSH浓度的犬红细胞（HK - 高GSH细胞）以及低钾和低（=正常）GSH浓度的正常犬红细胞（LK - 低GSH细胞）中的情况进行了比较。亚硝酸钠（NaNO2）诱导的高铁血红蛋白形成速率依次为：LK - 低GSH＞HK - 低GSH＞HK - 高GSH细胞，且在7分钟和15分钟时各组间差异显著。在含有葡萄糖的培养基中，HK - 高GSH细胞和HK - 低GSH细胞中的高铁血红蛋白还原都很快，还原速率比LK - 低GSH细胞高1.7倍。与还原的高铁血红蛋白量相当的丙酮酸积累表明，高铁血红蛋白主要通过与糖酵解偶联的NADH - 高铁血红蛋白还原酶进行还原。HK - 低GSH细胞显示出糖酵解速率增加和丙酮酸激酶活性高，类似于HK - 高GSH细胞中的水平。因此，很明显，HK - 低GSH细胞比LK - 低GSH细胞对血红蛋白氧化为高铁血红蛋白具有更大的保护作用，这是因为HK - 低GSH细胞中糖酵解速率增加，这归因于这些细胞中丙酮酸激酶活性高。
