[Ultrastructural organization of the brush alveocytes of normal and hypertrophic rat lungs].

In non-inbred male rats, 140-200 g of body weight, the left lung was removed. In the right lung of the experimental and intact animals, brush alveolocytes were revealed electron microscopically and their structural organization was stated 1, 3, 7, 30 and 274 days after the operation. It was stated that during the process of compensatory hypertrophy in the lung, the occurrence rate of these cells increased considerably. In controls only 3 such cells were revealed, while in the experiment, the number of the brush alveolocytes was 20. In the experiment, most of the cells had signs of hyperfunction: increased amount of pinocytic vesicles in the apical part of the cell, dilated canaliculi in granular cytoplasmic network, formation of "laminar" structures from the membranes of the canaliculi of the granular cytoplasmic network. The brush alveolocytes were especially active during the period of acute alveolar hypertrophy (5-7 days after the operation) and correlated with the state of alveolar surfactant. The data obtained supported the hypothesis on chemoreceptor nature of the cells in question and demonstrated their participation in regulation of alveolar surface tension.