[The effect of nedocromil sodium on the luminal-dependent chemiluminescence of whole-blood leukocytes].

Nedocromil sodium in concentrations of 10(-3) to 10(-9) M dose-dependently inhibits a zymosan (2 mg/ml)-induced chemiluminescence response (CLR) of whole blood leukocytes and, to a lesser extent, phorbol myrystate acetate (PMA)-induced CLR. The count of diformazan-positive granulocytes in the zymosan-induced nitroblue tetrazolium test slightly reduced in the presence of 10(5) nedocromil sodium. PMA in a dose of 10(-9) M did not induce CLR, but brought about leukocyte priming, thus sensitizing them to secondary triggering by suboptimal zymosan concentrations (0.5 mg/ml). A subsequent stimulation of leukocytes with PMA + zymosan demonstrated that nedocromil sodium (10(-7) M) inhibited mainly priming PMA rather than the zymosan-triggering step of leukocyte activation.