Abstract
In order to elucidate the role of mucopolysaccharides in gallstone formation, two kinds of calcium carbonate stones were submitted to examination. Sample I was a simple calcium carbonate stone and Sample II a mixture of calcium carbonate-mantles obtained from three gallstones which had small cholesterol stones in their central parts and were covered by thick calcium carbonate mantles. The crude mucopolysaccharides in both samples resembled each other in then chemical compositions, containing hexose, hexosamine and peptide as the major components, and L-fucose, uronic acid, sialic acid and sulfate as the minor ones. These preparations were fractionated by column chromatography on DEAE-Sephadex A-25, eluting stepwisely with increasing molarity of NaCl solution. The crude mucopolysaccharide from Sp. I was fractionated into 0.1M Fr., 0.7M Fr. and 1.5M Fr., of which 0.1M Fr. was predominant. On the other hand, the crude mucopolysaccharide from Sp. II was fractionated into 0.1M Fr. and 0.7M Fr. as the major fractions, and 0.5M Fr. and 1.25M Fr. as the minor ones.
The mucopolysaccharide in 0.1M Fr. consisted of hexose (galactose and mannose), hexosamine and L-fucose. In addition to these components, uronic acid and sialic acid were contained in 0.5M Fr., and uronic acid, sialic acid and sulfate in 0.7M Fr. Each acidic fraction was shown to be a mixture of two mucopolysac-charides by electrophoresis on cellulose acetate strips. However, their mobilities and metachromatic figures, together with their analytical data, indicated that 0.1M Fr. contained a neutral mucopolysaccharide; 0.5M Fr., a small amount of neutral mucopolysaccharide and a large amount of hyaluronic acid; 0.7M Fr., a small amount of chondroitin sulfate-like substance and a large amount of another unidentified acid mucopolysaccharide; 1.25M Fr., a large amount of chondroitin sulfate-like substance and a small amount of unidentified acid mucopolysac-charide; and 1.5M Fr., two unidentified acid mucopolysaccharides.
The acid mucopolysaccharides found in the gallstones were assumed to play a bridging action in the coagulation of calcium carbonate particles.
