Effects of biliary obstruction on pulmonary ultrastructure in the rat.

Hypoxemia and respiratory alkalosis have been described in patients with liver disease. Since no pulmonary parenchymal lesions have been related to the abnormal respiratory function, the effects of common bile duct ligation and division on pulmonary alveolar structure were studied in ninety-two 10- to 14-week-old male Wistar rats. In comparison with controls, the rats with ligated common bile ducts (CBD) developed progressive hepatic and pulmonary changes. The hepatic damage consisted of bile duct proliferation, loss of hepatocytes and generalized cirrhosis. Most pronounced pulmonary histologic differences between the CBD and sham-operated rats were thickening of interalveolar septa and generalized increase in cellularity of alveolar walls. With electron microscopy, frequently observed alterations included swelling and increased vacuolization of endothelial and epithelial (Type I) cells, proliferation of Type II alveolar pneumonocytes, and increase in amounts of collagen fibers and edema of the interstitium.