[A histochemical study of acid glycosaminoglycans on normal and pathological cartilage, ligaments and several other connective tissues]

Histochemical estimation of acid glycosaminoglycan was critically re-evaluated, using the meniscus, intervertebral disc, ossified yellow ligament, ganglion, Dupuytren's fascia and several other tissues. Each tissue was stained with toluidine blue, alcian blue, high iron diamine, low iron diamine, aldehyde fuchsin and dialyzed iron-ferrocyanide. Digestion techniques for GAG were used in these staining methods, and the effects of protease inhibitors (PI) on digestion were also examined. In this study, the optimal temperature for digestion with Streptomyces hyaluronidase was between 37 degrees C and 43 degrees C, which varied according to the tissue examined. The addition of PI seemed necessary because the enzymatic treatment without PI resulted in an excessive decrease of staining. Protease-free chondroitinase ABC, which did not excessively decrease staining results, was found to be more useful than chondroitinase ABC without PI.