Concentration of Cyclic Adenosine 3′,5′ -Monophosphate in Human Leucocytes during Phagocytosis

CYCLIC adenosine 3′,5′-monophosphate (cyclic AMP) has been established as a mediator of various hormonal effects in the appropriate target cells¹. Adenyl cyclase converts adenosine triphosphate (ATP) to cyclic AMP and is widely distributed in the membrane of mammalian nucleated cells^2–4. Since the early process of phagocytosis involves the physical and chemical contact of the cell membrane to the objects and subsequent formation of phagosome, we postulated that one of the earliest biochemical changes during phagocytosis might be an activation of adenyl cyclase and an alteration of concentrations of cyclic AMP in the phagocytes.