Collagen production by rat liver fat-storing cells in primary culture.

Morphological changes, proliferation and collagen synthesis of fat-storing cells (FSC) in primary culture were examined. FSC, isolated from rats treated with vitamin A, showed numerous large lipid droplets in the cytoplasm and positive desmin staining. After 4-7 days culture, these cells were transformed into fibroblast-like cells with a gradual depletion of lipid droplets and with abundant well-developed rough endoplasmic reticulum. The proliferation analysis revealed that DNA synthesis preceded the increase of cell number. Enhancement of the collagen synthesis by FSC were associated with the morphological change of the cells. Quantitative analysis revealed that these cells produced mainly type I collagen (84%) and a small amount of type III collagen (16%).