[Role of mitochondrial membrane lipid hydrolysis in their swelling induced by thyroxine].

The thyroxin-induced mitochondrial swelling was accompanied by an accumulation in organellas of free fatty acids which level was restored after the mitochondria contraction in the ATP presence. EGTA induced mitochondrial contractions as well, but with no free fatty acids utilization. Apparently, the thyroxin-induced mitochondrial swelling is the result of the membrane phospholipase activation and of the increase in the membrane cationic permeability due to the hydrolysis of membrane phospholipids.