[Localization of beta-glucuronidase in human mouth mucosal epithelium]

The authors investigated the activity of beta-glucuronidase in the mucous membrane of the alveolar process and in the buccal mucous membrane under light and electron microscopes. Demonstration of the enzyme was performed by means of a modification of the method of Hayashi. Under the light microscope enzymatic activity was demonstrated in both types of epithelium, particularly in the fibroblasts of connective tissue, higher activity being found in vascular walls, inflammatory infiltrates and particularly in macrophages. Findings in the epithelium were positive only in the stratum basale and the lower layers of the stratum spinosum. Submicroscopically activity of the enzyme was apparent in all layers of the epithelium, particularly in primary and secondary lysosomes and in cisternae of the granular endoplasmic reticulum, and only rarely in Golgi complex. There were only a few positive structures in the surface layers of the epithelium. Activity was lower in the buccal mucosa than in the alveolar epithelium. In the mucosa of the oral cavity the enzyme probably has a role in the degradation of proteoglycans.