Angiogenesis of Cultured Rat Sinusoidal Endothelial Cells

We have previously shown that rat sinusoidal endothelial cells cultured on Matrigel presented a great number of tube-like structures, forming a network, on the surface of the gel. In the present study, using this model, mimicking angiogenic processes that occur in vivo, we examined the effects of growth factors on these tubelike structures, and also the effects of extracellular matrices. Isolated sinusoidal endothelial cells were plated on culture dishes coated with type-1 collagen or Matrigel. Cultured sinusoidal endothelial cells were incubated in a medium containing various growth factors (a-FGF, b-FGF, HGF, and VEGF). Ultrastructurally, tube-like structures were formed by two or three sinusoidal endothelial cells which retained many endothelial pores on the cell surface. In morphometric analysis, acidic fibroblast growth factors (a-FGF), basic fibroblast growth factors (b-FGF), and especially hepatocyte growth factors (HGF) accelerated the formation of the tube-like structures. Vascular endothelial cell growth factor (VEGF) did not stimulated the formation of the tubes. These results suggest that growth factors which promote tube-like structures in cultured sinusoidal endothelial cells may induce regeneration of sinusoids in vivo.