Effect of phagocytosis on the carbohydrate metabolism of polymorphonuclear leucocytes

Abstract

1. 1. The changes in glucose metabolism in phagocytosing polymorphonuclear leucocytes have been investigated during conditions of maximal respiratory stimulation. 2. 2. From the conversion of the 14C from [i- 14C]glucose and [6- 14C]glucose to CO 2 and to lactate it can be calculated that the phosphogluconate-oxidation pathway becomes the main catabolic route for glucose. 3. 3. The 14CO 2 production from C-1, C-2, C-6 and uniformely labelled glucose indicates and increased recyclization in the pentose cycle and a stimulation of the Krebs cycle 4. 4. The 14CO 2 production from [6- 14C]glucose is inhibited by Amytal both in resting and in phagocytosing leucocytes, whereas that from [1- 14C]glucose is slightly inhibited in resting cells and becomes Amytal-insensitice during phagocytosis. 5. 5. By comparing the amount of glucose catabolized through the hexose monophosphate pathway and the amount of lactate produced, it is conlcuded that the stimulation of the hexose monophosphate pathway cannot depend on a NADPH 2-linked production of the extra lactate which accumulates during phagocytosis. 6. 6. The mechanism of reoxidation of the NADPH 2 and stimulation of the hexose monophosphate pathway activity during phagocytosis is discussed.