Increase of the breakdown potential of liposomes created from the lipids of liver mitochondria of rabbits with hypothyroidism

: Stability of the membranes of liposomes obtained from liver mitochondrial lipids of normal and thyroidectomized rabbits was examined by the electric breakdown method. It was examined by the electric breakdown method. It was discovered that in hypothyrosis, the breakdown potential increases, while the net negative charge on the surface of liposomes diminishes as compared to the samples of mitochondrial lipids obtained from normal animals. The changes in question returned to normal approximately 40 hours after a single administration of L-thyroxin (300 micrograms/kg bw). Addition of thyroxin in vitro (10(-5)-10(-7) M) exerted no effect on the test characteristics of liposomes, but at a concentration of 10(-4) M the hormone increased the breakdown potential and reduced the magnitude of the net negative charge on the surface of lipid vesicles. It is assumed that the changes seen in the electrical parameters of liposomes during hypothyrosis are associated with modifications in the index of fatty acids unsaturation and in the phospholipid spectrum of mitochondria.