Histochemical Analyses of Glycosaminoglycans in the Dermal Connective Tissues of Indian Air-breathing Freshwater Teleosts by Means of a Sensitized High Iron Diamine ( S-HID ) Technique

ln the dermal connectiv巴 tissu邸 oflndian air-breathing freshwater teleosts‘ the molecular species of glycosaminoglycans have been studied by means of newer histochemical staining and enzyme digestion procedures with or without urea treatment. The staining procedure used was a sensitized high iron diamine (S-HID) procedure, whereas the enzymes employed were chondrOltllase ABC and keratanase. According to the results obtained、isomencchondroitin sulfates and keratan sulfate were the primary glycosaminoglycan molecular species contalned in the dermal connectlve tissues ofthe freshwater teleosts and th巴formermolecular species were apparently masked by col1agens in the tissues. These findings are taken to suggest that the glycosaminoglycan molecular speCles and their specific interactions with collagenous fibers are associated wlth the assistance of cutaneous respiration and protection of the bodies仕omhostile environments in the fishes.