Abstract
It was found that three niacin-related compounds, isonicotinic acid, nicotinamide, and nicotinamide N-oxide, induced granulocytic differentiation in HL-60 cells. We investigated the expression of CD38, which catalyzes the synthesis of cyclic ADP-ribose, a Ca2+ mobilizer, during differentiation by niacin-related compounds. It was found that CD38 was induced by isonicotinic acid, whereas nicotinamide and nicotinamide N-oxide containing an amino group did not induce it. The difference in expression of CD38 may provide some useful information for the elucidation of the mechanisms of cell differentiation.