Formation of Leukotrienes From Calcium Ionophore-A23187 Stimulated Rabbit, Rat and Mice White Blood Cells

Leukotrienes (LTs) producing capacity was investigated in calcium ionophore A23 187- stimulated rabbit. rat and mice peripheral white blood cells suspension. A reverse phase high performance liquid chromatography technique and computerized UV spectroscopy were employed to isolate and quantitate the released LTs namely. LTC₄ and LTB₄. Preincubation of rabbit white blood cells at 37°C for 5 min followed by calcium ionophore-A23 187 (1 pM) stimulation for another 5 min produced an equal amounts of LTC₄ as compared to LTC₄ produced by human white blood cells (105±11 versus 95±9.5 pmol/10⁷ cells respectively; mean ±SEM). In contrast rabbit white blood cells synthesized significantly lower LTB₄ in comparison with LTB₄ produced by peripheral white blood cells from healthy control (168±18 versus 228±19 pmol/10⁷ cells respectively: mean ±SEM). When rat and mice white blood cells suspension were stimulated with calcium ionophore A23187 (1 µM) after preincubation at 37°C for 5 min, equivalent amounts of LTC₄ and LTB₄ were observed. However, LTB₄ and LTC₄ produced by rat and mice white blood cells were significantly lower in comparison with LTB4 and LTCj produced by human white blood cells stimulated with calcium ionophore-A23 187. These results demonstrate that rabbit. rat and mice white blood cells suspension possess the capacity to produce LTC₄ and LTB₄ from endogenous substrate after calcium ionophore-A23 187 stimulation.