Adenosine synthesis was studied during 2-deoxyglucose-induced ATP catabolism in intact rat polymorphonuclear leucocytes. When both adenosine kinase (EC 2.7.1.20) and adenosine deaminase (EC 3.5.4.4) were selectively inhibited, adenosine accumulated. Adenosine formation took place inside the intact cells by a metabolic pathway independent of the ecto-5′-nucleotidase (EC 3.1.3.5). Distinct metabolic pathways are proposed for adenosine production from intracellular or extracellular nucleotides.
