Glycosaminoglycan staining in diseasesed dog skin.

Diseased skin of dogs was stained using the critical electrolyte concentration-Alcian Blue method, PAS methods, and the high iron diamine technique. Digestion with testicular hyaluronidase and chondroitinase was also used to evaluate the staining results. Diseased skin exhibits a tendency for the glycosaminoglycans to revert to the condition seen in juvenile normal skin: epidermal glycoprotein content falls, total glycosaminoglycan content and the proportion undigested by hyaluronidase rises, and sulphation falls. In collagen, both hyaluronidase-stable material and sulphation increase, but follicle basement membrane does not show this trend towards the juvenile state.