Retinoic acid alters the metabolic 3H-labelling of glycosphingolipids.

Retinoic acid increases the incorporation of radioactivity from a mixture of [3H]-galactose and [3H]-glucosamine into glycosphingolipids of serum-starved quiescent human foreskin fibroblasts with a preferential labelling of ceramide mono- and dihexoside as compared to ceramide tri- and tetrahexoside. Under the conditions used, no similar change in the specific labelling of glycoprotein is observed. Alteration in [3H]-precursor uptake into glycolipids comparable to that seen under the influence of retinoic acid does not occur in the presence of phorbolester, colchicine, butyrate or after infection with cytomegalovirus.