[Pulmonary and bronchial blood circulation under conditions of changed gaseous environment]

By means of ultrasonic method used in acute experiments on cats with closed chest under normal respiration the authors studied the blood flow in left low-lobar pulmonary artery and vein and in bronchial artery, as well as the blood pressure in pulmonary and femoral arteries in inhalation of next gaseous mixtures: 7.5% O2 in nitrogen; 30% O2; 3% CO2; 21% O2+ +79% He; 30% O2 + 67% He + 3% CO2. It was shown, that inhalation of the normoxic gaseous mixture, in which nitrogen is replaced by helium, did not call significant changes in pulmonary and systemic circulation. However, the presence of the helium in complicated gaseous mixture can change the reactivity of pulmonary and bronchial vessels to influence the components participating in these complicated gaseous mixtures.