Vasoconstriction and Remodeling in Pulmonary Hypertension

¹ From the Departments of Pathology and Medicine, Pulmonary Circulation Center, B-1308, Medical Center North, Vanderbilt University School of Medicine, Nashville

In one group of sheep, Escherichia coli endotoxin was given intravenously three times per week for ten weeks, and in another group the cyclooxygenase inhibitor indomethacin was given subcutaneously two times per day for three weeks. Both groups developed the structural and functional changes of modest but sustained pulmonary hypertension and showed granulocyte sequestration in the peripheral lung. Indomethacin enhanced pulmonary vasoreactivity, but endotoxin depressed reactivity transiently. Prolonged inflammation of the lung may be associated with alterations in vasoreactivity and the development of chronic pulmonary hypertension.