[Analysis of pulmonary vasomotor responses to alveolar hypoxia and hypercapnia].

In acute experiments on cats responses of the lung vessels to hypoxic and hypercapnic stimuli and the latters effect on minor circle hemodynamics were studied as well as the role of changes of the blood acid-alkaline balance and volume of ventilation in potentiation and blocking of the above responses. The alveolar hypoxia and hypercapnia being induced a reversed dependence between the relative mass of the lung area and reduction of its blood flow vasdseined Hyperventilation with hypoxic gas mixture inhibited the hypoxic vasoconstriction in respective lung area which seems to suggest a shift towards alkalosis of the blood in the area of gases respiratory diffusion. The autoregulation of the lung gas exchange is supposed to be the function of the respiratory dead space.