[Mechanisms of disorders of the bioenergetic functions of mitochondrial membranes in hypoxia].

Evidence is provided that the following events take place in the cell in hypoxia and reoxygenation: expenditure of residual oxygen; a fall in the level of macroergic compounds; entry of calcium ions into the hyaloplasm both from the outside and from the mitochondria; activation of mitochondrial A2 phospholipase (possibly along with the other phospholipases); increase of membrane ion permeability (first phase of separation). This stage corresponds to the "irreversibility point" in cell damage because if the supply of oxygen to the cell is restored after it, the cell will not "recover" but, instead, will be damaged still more. This occurs as the result of active swelling of the mitochondria, inhibition of respiration and bioenergetic functions (the second stage of separation and loss of Ca-accumulating property by the mitochondria), irreparable damage to the cell with autolysis.