Estimation of Glucose-6-phosphate Dehydrogenase in Sheep Erythrocytes

Abstract

IN this mild controversy it is worth recalling that Somogyi¹ long ago found that the total glycolytic activity of sheep blood is only 20–30 per cent of that of human blood. Leng and Annison² have recently shown that glucose only in rare cases penetrates into sheep erythrocytes. But they also observed that of the low glucose metabolism which does take place in these red cells 15 per cent goes through the pentosephosphate pathway; when stimulated by methylene blue, the fraction rises to nearly 100 per cent. These findings implicate the presence of glucose-6-phosphate dehydrogenase in the cells, but the concentration is clearly so low that it escapes detection with the rather crude methods we use for convenience in our surveys of human populations. This particular feature of sheep red cells is probably only another aspect of the peculiar carbohydrate metabolism in these animals.