In the conditions of inflammation and hypoxia the destructive processes are noted in all cells of the air-blood barrier, basement membranes and in the interstitium. The basis of pathological processes in cells with short and long lives cycles are violations of the energy metabolism in mitochondria. Structural and functional characteristics of long-living cells promote the greater resistance to oxygen deficiency. The increase in the number of poikilocytes among red blood cells in the alveolar capillaries may serve as an indicator of local hypoxia.