Fig. 9.

Effects of TNF-α, LTB₄, and TXA₂ analog U-46619 in cultured cardiomyocytes and isolated neutrophils. A: TNF-α (50 ng/ml)-induced TUNEL-positive nuclei in cultured cardiomyocytes. TUNEL-positive nuclei were counted after incubation for 12 h with vehicle or TNF-α. B: extracellular release of arachidonic acid from cultured cardiomyocytes in response to TNF-α. Cardiomyocytes prelabeled with 0.5 μCi/ml [³H]arachidonic acid were treated for 12 h with vehicle or TNF-α (50 ng/ml). The radioactivity in the supernatant was measured in a scintillation spectrometer. The activity was expressed as the percentage of total cell radioactivity. The content was calculated by dividing by the amount of cellular protein. C: TUNEL-positive nuclei in cultured cardiomyocytes after incubation for 12 h with TXA₂ analog U-46619 (100 nM) or LTB₄ (100 nM). D: extracellular release of arachidonic acid from isolated peritoneal neutrophils in response to TNF-α (50 ng/ml) alone for 20 min or in combination with N-formyl-methionyl-leucyl phenylalanine (fMLP, 1 μM) for an additional 20 min. *P < 0.01 and †P < 0.05 compared with vehicle; n = 6∼8 mice in each experiment.