| Abstract: | The surface activity of seven successive washings from the right lung, determined with the aid of a modified Wilhelmy balance, was the same as in the control until the 5th day after removal of the left lung and also in the late stage after the operation ( min = 23–24 dynes/cm). Intracellular edema of the components on the air-blood barrier and the escape of edema fluid into the lumen of the alveoli of the  vesicles were not reflected in the surface-active properties of the lung surfactant. A sharp increase in size of the alveoli on the 5th–7th day after the operation was accompanied by an increase in the surface-active properties of the lung washing (min = 11–15 dynes/cm) and by increased secretion of material of the osmiophilic lamellar bodies from the type II alveolar cells into the lumen of the alveoli. The cytological mechanisms of the increased production of surfactants in the hypertrophied alveoli are activation of lipid synthesis in the type II alveolar cells, hypertrophy of those cells, and the appearance of binuclear cells.Laboratory of Growth and Development, Research Institute of Human Morphology, Academy of Medical Sciences of the USSR. Laboratory of Physiology, A. V. Vishnevskii Institute of Surgery, Academy of Medical Sciences of the USSR, Moscow. (Presented by Academician of the Academy of Medical Sciences of the USSR A. P. Avtsyn.) Translated from Byulleten' Éksperimental'noi Biologii i Meditsiny, Vol. 83, No. 2, pp. 169–172, February, 1977. |
