In awake rats with indwelling catheters, the development of pulmonary hypertension after feeding Crotalaria spectabilis seeds is followed. Hypoxemia is excluded as a factor. Other hemodynamic changes are found before hypertension. After 7 days, pulmonary artery pressure (Ppa) is normal, 17.17 +/-
The early changes in pulmonary artery structure and the timing and development of right ventricular hypertrophy were examined in rats after ingestion of Crotalaria spectabilis; the arteries were distended with a Micropaque--gelatin mixture. The earliest change, detected at Day 3, is the appearance