Pulmonary endocrine cells in different varieties of pulmonary vascular disease.

The rôle of the endocrine cells which populate the airways of the lung is uncertain, although it has been suggested that one of their functions might be to regulate the pulmonary vasculature. We have studied the number, content and distribution of these cells in 26 pairs of lungs removed during heart-lung transplantation for the treatment of pulmonary hypertension of various causes, none of which were characterized by plexogenic arteriopathy. In comparison with the controls, there were no differences in the number, content or distribution of these cells, although in two cases of recurrent pulmonary thromboembolism they were aggregated into abnormal disorderly clusters.