The purpose of this study was to isolate endothelial cells from different organs of porcine fetuses and to examine the binding of endothelial markers including lectins. Endothelial cells were isolated from the aorta, cerebral cortex, myocardium, ovary and testis. Binding of the antibodies to von Willebrand factor (vWF) and angiotensin converting enzyme (ACE), the presence of Weibel Palade bodies (WPB), uptake of acetylated low density lipoprotein (acLDL), and labelling with the lectins Bandeiraea simplicifolia agglutinin I (BS I), Peanut agglutinin (PNA), Dolichos biflorus agglutinin (DBA) and Ulex europaeus agglutinin I (UEA I) were examined. Cell preparations displayed cobblestone-like morphology with the exception of testicular endothelium, which formed arcuate structures. Endothelium isolated from the brain labelled more strongly than any other cell line with the lectin PNA, but it did not express ACE. In contrast to other cell preparations, myocardial endothelium showed very low binding of anti-vWF. Ovarian endothelium was able to perform in vitro angiogenesis. Moreover, these endothelial cells possessed the largest number of WPB. Testicular endothelium displayed highest binding of vWF. Endothelium isolated from the aorta, in contrast to all other endothelial cells, did not take up acLDL. These results demonstrate that organ- and tissue-specific heterogeneity is already expressed in fetal endothelium.