FURTHER DATA ON INTRACELLULAR STRUCTURES OF HUMAN SALIVARY-GLANDS - ASEM STUDY

Specimens of human salivary glands have been studied by our modificati on of the AODO maceration method which, carried out on sections of con trolled thickness, allows the analytical study of human bioptical mate rial. Lately, our technique has been further improved and simplified b y omitting the treatment with dimethylsulfoxide and by using osmium-fe rrocyanide as secondary fixative. Following maceration with diluted Os O4, some of the sections also were shaken for 10 - 15 min with a rotat ing agitator. Already at low magnification, all parenchymal cells were clearly distinguishable for their complement of cytoplasmic organelle s. Serous cells and mucous cells at the beginning of their secretory c ycle were characterized by well developed RER and Golgi apparatus, whi le mature mucous cells exhibited only scanty organelles compressed amo ng the secretory droplets. Mitochondria were tubular, and often branch ed and convoluted When sectioned, these organelles, besides the usual plate-like cristae, showed tubular cristae as well. The SER of striate d and excretory duct cells was well developed and consisted of a netwo rk of smooth anastomosing tubules in the apical cytoplasm where it pro bably represented the transcellular pathway for ion transport. In spec imens subjected to shaking, cytoplasmic organelles were occasionally r emoved allowing a nonobstructed view of the inner side of the plasmale mma and its specializations. With this technique the intercellular can aliculi of serous cells also became appreciable front their cytoplasmi c side. They appeared as ribbon-like irregular protrusions with walls fenestrated by holes, corresponding to the interior of microvilli depr ived of the cytoskeleton, and, sometimes, with lateral expansions poss ibly related to the mechanism of exocytosis. Results reported here cle arly showed the usefulness of the maceration method in providing addit ional data on the cytoarchitecture of epithelial cells of salivary gla nds. Furthermore, by allowing the visualization of internal surfaces p reviously hidden to direct inspection, our technique may open new hori zons in morpho/functional studies of human salivary glands.