Growth response of endothelial and smooth muscle cells to a collagen matrix throughout development

The in vitro response of chick embryo endothelial and smooth muscle cells from aorta explants, induced to grow on a collagen type I matrix, was investigated at different stages of development. At early stages of embryonic development both cell types reacted with collagen as a substratum. At later stages, the endothelial cells had a lower response, whereas the response of muscle cells remained constant. Further evidence is given for the spatial-specific behaviour demonstrated by endothelial cells, which remained on the surface while smooth muscle cells invaded the matrix. Results further highlight the possible role of endothelial cell polarity on the cell-collagen interaction and growing response.