Figure 1.

Lung formation and branching morphogenesis of the lung in an explant system of rat foregut. Foreguts of rats were harvested at 11 days of gestation and cultured in a semidry system. Pictures representative of a series of experiments of untreated (A−D), vehicle DMSO-exposed (E−H) and Nitrofen-exposed (I−L) foreguts developing into branching lungs are shown at culture day 0 (A, E, I), 2 (B, F, J), 6 (C, G, K), and 8 (D, H, L), respectively. The Nitrofen-exposed group was exposed to Nitrofen in a concentration similar to that used in vivo: 0.25 mg.200 μl⁻¹ medium on the first culture day, and to half of this on the second culture day. Lung formation in this group occurred at the same time point as in the control groups (J), which were cultured in medium with vehicle DMSO (F) or in medium alone (B). Branching morphogenesis was clearly reduced in the explants exposed to Nitrofen during the remaining culture period (L). Arrow indicates lung. All images at same magnification.