A COMPARISON BETWEEN DIFFERENT MUCOPOLYSACCHARIDE STAINS AS APPLIED TO CHICK EPIPHYSEAL CARTILAGE

Abstract

The localization of the periodic acid-Schiff reaction, of toluidine blue metachromasia, of alcian blue staining and the Hale reaction do not coincide in the epiphyscal cartilage of the chick. The iron-adsorption pattern of the Hale reaction corresponds to that of Ca45 uptake in vitro and represents probably a binding fraction of cartilage, or unbound chondroitin sulfate. Toluidine blue metachromasia is less specific and may well represent collagen-bound as well as unbound sulfated mucopolysaccharides. The PAS stained material predominates in the articular cartilage and in the zone of large cells of the conjugation cartilage. Its intimate distribution matches the pattern of high density revealed by alpha-radiography. It is probably a protein-bound high polymer. The intracellular and immature matrix distribution of alcian blue points to its staining of a precursor component, probably nonsulfated. The existence of an interlacunar network of periodic acid Schiff reactive and alcian blue stained fibers in the articular cartilage has been confirmed.