Effects of metabolite VIII of bromexine (Na 872) on type II epithelium of the lung: an experimental and morphological study with reference to surfactant secretion.

50 Wistar rats were divided into 5 groups: 4 experimental and 1 control group. The experimental groups A and B received, per os, a daily dose of 100 mg of Na 872 (metabolite VIII of Bromexine) for 3 or 6 days and were killed 1 day later. The experimental groups C and D received 200 mg of the same substance according to the same experimental procedure and for the same periods. The lungs were fixed in situ by perfusion, examined by light and electron microscopy using morphometric methods. No manifest lesions occurred in alveolar tissue. Morphometric analysis showed an increase in the volume ratio of type II epithelial cells and of lamellated body volume in respect to total alveolar tissue volume. Furthermore, our findings suggested an increase in lamellated bodies in respect to type II cell volume, particularly in group C (200 mg/3 days); they showed the existence of a hypertrophy of type II cells, particularly at 6 days.