Fig. 1.

Response of the ductus arteriosus (DA) to inflammatory stimuli. A: representative images of the postnatal DA at 4 h of age (arrows). The DA was closed in uninjected control mice; impaired DA closure was observed in newborn mice after cecal slurry injection but not in mice injected with 1 mg/kg LPS. AO, aorta; PA, pulmonary artery. B: exposure of the isolated, pressurized term gestation mouse DA to increasing concentrations of LPS did not alter its vasomotor tone. Data shown as mean ± SE.C: representative tracing showing that prolonged exposure (24 h) to LPS did not inhibit response of the isolated, pressurized DA to an initial stimulus with 50 mM KCl or to graduated doses of KCl (from 50 to 12.5 mM) or the thromboxane mimetic U-46619 (10–100 nM).