Search

The cystic fibrosis transmembrane conductance regulator (CFTR) is a cyclic AMP-dependent protein kinase (PKA)-regulated Cl channel, crucial for epithelial cell regulation of salt and water transport. Previous studies showed that ezrin, an actin binding and A-kinase anchoring protein (AKAP), facilitates association of PKA with CFTR. We used immunohistochemistry and immunogold transmission electron microscopy to localize CFTR, ezrin, and PKA type II regulatory (RII) and catalytic (C) subunits in striated duct cells of human parotid and submandibular glands. Immunohistochemistry localized the four proteins mainly to the apical membrane and the apical cytoplasm of striated duct cells. In acinar cells, ezrin localized to the luminal membrane, and PKA RII subunits were present in secretory granules, as previously described. Immunogold labeling showed that CFTR and PKA RII and C subunits were localized to the luminal membrane and associated with apical granules and vesicles of striated duct cells. Ezrin was present along the luminal membrane, on microvilli and along the junctional complexes between cells. Double labeling showed specific protein associations with apical granules and vesicles and along the luminal membrane. Ezrin, CFTR, and PKA RII and C subunits are co-localized in striated duct cells, suggesting the presence of signaling complexes that serve to regulate CFTR activity. [ABSTRACT FROM AUTHOR]

After reviewing the successive phases of lithogenesis, from dyschylia to outright calculosis, the clinico-epidemiological data on 400 cases of salivary calculosis with incidence according to location (94% submandibular, with 72% intraductal calculi), sex (70% male), age (86% between the second and fifth decades), concomitant pathologies (diabetes mellitus in 25% of cases, arterial hypertension in 20% of cases, chronic hepatopathies in 10% of cases) are presented. The morphological and microstructural aspects of the calculi, observed in polarised light under the optical microscope are reported. The scanty quantity of inorganic tissue contained and the presence of multiple and multidirectional growth nuclei in every calculus examined are pointed out.