[Functional morphology of vessels in the distribution of the pulmonary circulation of people adapted to the Northeast USSR].

Studies of the contrasted vessels of the lungs in practically healthy men who had lived in the north-eastern region of the USSR over 3 years and who had died of casual causes in Magadan were carried out by stereoroentgenogrammetry and morphometry. The studies revealed a rearrangement of the distribution arteries of the lesser circulation according to the hypervolemic type: a reliable dilatation of the lumen, thinning of the walls of the right pulmonary artery, superlobar trunk, branches of the segmentary arteries of the superior and middle lobes of the lung. The pronounced desorganization and perish of elastic laminae in the wall of the stretched arteries were compensated by the appearance of layers of the smooth muscles -- by the so-called hypermuscularization of arteries of the elastic type. The enlarged capapcity and intensification of the blood flow in the arteries of the superior and middle lobes of the lung represented an important mechanism of adaptation of the lesser circulation in man under extreme climatic conditions in the north-eastern region of the USSR.