Anaphylactic Release of Prostaglandins from Human Lung in vitro1–4

Fragments of human lung parenchyma were passively sensitized with ragweed IgE in vitro, and subjected to antigenic challenge in experiments designed to explore the genesis of arachidonate metabolites during lung anaphylaxis. Lung supernatant was sampled serially and examined for histamine as a marker of mast cell activation, and prostaglandins E2, F2α, and 13,14-dihydro, 15-keto-PGF2α. In eight of nine human lung experiments, the kinetics of PGE2 and PGF2α production were indistinguishable from that of histamine release. In all experiments PGF2α production (40.7 ± 7.1 ng PGF2α/g of lung tissue) was large compared with PGE production (4.0 ± 1.0 ng PGE/g of lung tissue). When lung fragments were challenged with high concentrations of 3 smooth muscle contractants (histamine, methacholine, and KCl), PGF2α production was only 5 to 20% of that seen with optimal antigenic challenge of the same tissue. On this basis we concluded that neither released histamine, either directly or indirectly, nor smooth muscle con...