Role of cPLA₂ in LTB₄-induced Ca⁺⁺-dependent [³H]AA release.

Cells were preincubated for 5 minutes at 37°C and then stimulated for the indicated time with 100 nmol/L LTB₄. Panels A-C show representative blots obtained from 3 separate experiments. (A) Whole-cell lysates were probed, by Western blotting, with antibodies to cPLA₂. (B and C) Samples immunoprecipitated with the antiphosphotyrosine antibody 4G10 were then probed, by Western blotting, with antibodies to cPLA₂ (B) or lyn (C). (D) cells were preincubated in the presence (°) or absence (l) of 1 mmol/L Ca⁺⁺/1 mmol/L Mg²⁺ and the indicated concentrations of MAPF. Following stimulation with LTB₄ (100 nmol/L), the release of [³H]AA at 60 seconds was determined. Data represent the mean ± SEM of 3 to 4 independent experiments.