Morphological study of mast cell localization in the wall of the proximal tubule in the domestic swine kidney.

摘要

Kidney perfusion was carried out in six 8-month-old pigs and semi-thin and ultrathin sections were prepared after a routine treatment. Light microscopy showed that mast cells were not frequently found. Most were localized in the wall of the proximalconvoluted tubule, while in the proximal straight tubule wall they were fewer in number. Most of the mast cells were oval in shape, their size being typical for this species, and the granules were reddish in colour. Three types of granule containing anevenly distributed granular-fibrous substance were found by transmission electron microscopy: (a) a single electron-optically dense belt under the membrane; (b) optically empty spaces between the substance and the cell membrane; (c) two parallel dense belts below the granular membrane. These latter were the smallest in size. Some of the granules of the first type were connected with the granular endoplasmic reticulum. A very narrow intercellular area and single desmosome-like junctions were found between the mast cells and the epithelial cells. Protrusions of plasmalemma and granules outside the cells were not established.