The effects of ibuprofen and diclofenac on the chemotaxis and adenosine triphosphate level of polymorphonuclear cells in vitro.

Investigations were carried out to determine the effect of ibuprofen and diclofenac on the chemotaxis of human polymorphonuclear cells. The experiments were done with the drugs alone as well as in the presence of leukotriene B4 (LTB4). A modified quantitative bioluminescence assay was used to measure chemotaxis, which allowed the calculation of differences in the spontaneous migration in contrast to the effects of the drugs, and simultaneously, also, the evaluation of whether the inhibition or augmentation of the chemotaxis was due to influences on the adenosine triphosphate (ATP) level of the cells. It was found that high concentrations (10 mM) of either ibuprofen or diclofenac destroy the intracellular ATP of polymorphonuclear cells (PMN). Therefore, the reported inhibition of the chemotaxis by ibuprofen at a concentration of 10 mM cannot be understood as a part of the chemotactic process. In the range of 1 microM and 0.1 mM ibuprofen and diclofenac did not statistically affect the intracellular ATP level of PMN cells but at the same time a distinct inhibition of the chemotactic response of PMN cells was observed. This effect occurred even in the presence of a potent chemoattractant (leukotriene B4). Ibuprofen (0.1 mM) reduced chemotaxis to 67% and the same concentration of diclofenac reduced it to 56% of the values of LTB4 alone.