Transmission electron micrograph of liver sinusoidal endothelial fenestrae in New Zealand White rabbits. The endothelial lining is cut tangentially and shows the occurrence of fenestrae (f) mostly in groups, called sieve plates. To the left and the right hand side of the picture, we find the space of Disse (Sd) with sparse microvilli (mv) protruding from parenchymal cells. The right top corner of the picture shows the lumen (L) of the sinusoid. The right bottom part of the picture shows the cytoplasm of a parenchymal cell.