Calcium-ionophore A23187 induces dual changes in the release of 5-lipoxygenase and cyclooxygenase products by macrophages.

ABSTRACT

A23187-treated murine peritoneal macrophages release increased quantities of the immunoreactive 5-lipoxygenase metabolite leukotriene B4 (LTB4) and the immunoreactive cyclooxygenase products 6-keto prostaglandin F1 alpha (6-keto PGF1 alpha) and thromboxane B2 (TXB2) during a 40 min incubation period. The increase in release of LTB4 was marked already after 5 min of incubation and was maximal after 20 min. The increase in release of 6-keto PGF1 alpha and TXB2 started in most cases after 5 min of incubation and augmented gradually up to 40 min after incubation. The ratio of the increase of LTB4/6-keto PGF1 alpha and of LTB4/TXB2 revealed an increase in favor of LTB4 in the first 5 min of incubation.