part of endothelial cell fenestrated endothelial cell endothelial cell of sinusoid endothelial cell of hepatic sinusoid liver sinusoidal endothelial cell endotheliocyte of hepatic sinusoid An endothelial cell that is part of the hepatic sinusoid. These cells possess flattened areas containing perforations about 0.1 micrometers in diameter, known as fenestrae. The fenestrae are arranged in groups known as sieve plates. BTO:000125 LSEC FMA:62911 hepatic sinusoid