DISTRIBUTION AND EVALUATION OF COMPLEX CARBOHYDRATES IN THE QUAIL COLLECTING DUCTS

The cell heterogeneity within the collecting duct epithelium of quail kidney was investigated using histochemical methods for complex carboh ydrates. The selective distribution of acidic glycoconjugates allowed further discrimination between metachromatic, mucin-secreting cells an d dark, proton-transporting cells. Enzymatic digestion by glycosidases was performed to characterize the carboxylated and sulphated glycocon jugates of mucin-secreting cells. The staining intensity of all histoc hemical reactions with and without prior treatment, was quantitated by means of scanning histophotometry and differences in absorbance value s were evaluated by statistical analysis. A different distribution of sulphated components was found for the mucin-secreting cells of renal cortex and medulla, suggesting a morphofunctional heterogeneity within mucin-secreting cell population.