Formation of Extracellular Adenosine Triphosphate by Human Erythrocytes

作者：Gunnar Ronquist · 发表于：Acta Physiologica Scandinavica · 年份：1968 · DOI：10.1111/j.1748-1716.1968.tb04270.x · 被引用次数：28 · 研究领域：Neonatal Health and Biochemistry、Adenosine and Purinergic Signaling、Pancreatic function and diabetes

Abstract The formation of extracellular adenosine triphosphate by human erythrocytes was studied. The red cells were incubated with (32P)‐orthophosphate, together with all necessary substrates and co‐factors of the glyceraldehyde‐3‐phosphate dehydrogenase and phosphoglycerate kinase reactions (complete system), and also with an incomplete system lacking the phosphorylated substrates and cofactors. Finally, the red cells were incubated with the complete system lacking only one phosphorylated cofactor. All incubations were performed under isotonic conditions. At I min incubation, three times more AP32P was formed by the red cells incubated with the complete system than with those incubated with the incomplete system. All the resulting AP32P formed by the added phosphorylated substrates and cofacton present in the complete system could be recovered in the extracellular medium. Only an insignificant part of this AP32P was probably formed by enzymes which were eluted out into the surrounding medium. It is therefore reasonable to infer that most of the AF32P present in the extracellular medium was formed by the enzymes located on the surface of the red cells. No AP32P was found in the extracellular medium of red cells incubated with the incomplete system, nor with the complete system lacking only one phosphorylated cofactor. Thus, none of the intracellular ADP, NAD+ or glyceraldehyde‐3‐phosphoric acid could be utilized in ATP formation on the red cell surface.