[The effect of high-altitude hypoxia on the lesser circulation in rats]

During ten-month stay at 3200 m altitude in the Tien Shan mountains a significant increase of systolic pressure and practically unchanged diastolic one in pulmonary artery were recorded in rats. A redistribution of the blood flow and volume occurred. An increased oxygen blood capacity was maintained through an elevated hemoglobin content in erythrocytes and an increase of their size but not of their number.