Biochemical analyses of EDTA extracts and collagenase digests from bone and skin of Wistar rats

Abstract

Using EDTA extraction and collagenase digestion, rat bone and rat skin were compared in terms of their content of hydroxyproline, hexoses, uronic acid, sialic acid and plasma proteins. The collagen content of the organic matrix from both tissues was similar. Greater differences were observed in the sialic acid and uronic acid content of the matrix, bone containing higher amounts; smaller differences were found in the levels of hexoses, albumin, IgG and α₁ acid-glycoprotein, which are higher in EDTA extracts from bone. The DEAE-cellulose chromatography of the EDTA extracts and soluble collagenase digests indicated the presence of a variety of glycoproteins and a proteoglycan fraction. An acidic glycoprotein, corresponding to sialoprotein, was present in bone but not in skin extracts.