[The hemodynamics of the lesser circulation and blood indices in rats under long-term high-altitude hypoxia].

Pulmonary hemodynamics in anesthetized rats was studied during long-term residence (2,5 and 10 months) at high altitude (3,200 m, Tien Shan). Transbronchial regional electroplethysmography and catheterization of pulmonary artery was used. It has been shown that at all periods of adaptation there was increased systolic pressure in pulmonary artery and practically unchanged diastolic one. Some regional redistributions of pulmonary blood flow and blood volume for five different lung parts were demonstrated. Hemoglobin content in erythrocytes was steadily increased while specific electric blood resistance, hematocrit, and number of erythrocytes did not change so significantly. The role of pulmonary arterial hypertension and changes of other studied indices of hemodynamics and red blood in adaptation to chronic high-altitude hypoxia are being discussed.