Old age is associated with ultrastructural changes in isolated rat liver sinusoidal endothelial cells

Old age is associated with ultrastructural changes in the hepatic sinusoid called pseudocapillarization, which include defenestration and thickening of the sinusoidal endothelium. We investigated whether such changes also occur in isolated and cultured liver sinusoidal endothelial cells. Liver sinusoidal endothelial cells were isolated from young (6-10 months, n = 4) and old (24-26 months, n = 4) F344 rats and fenestrations evaluated using scanning electron microscopy. Fenestration diameter was reduced in old age from 194 +/- 1 nm to 185 +/- 1 nm (P < 0.001) and there was an age-related increase in the number fused fenestrations and large gaps. Age-related changes in the diameter of fenestrations in the liver sinusoidal endothelial cell are maintained following isolation and culture. This suggests that this age-related change may be intrinsic to the liver endothelial cell and/or irreversible.