FINE STRUCTURE OF HUMAN PARATHYROID GLANDS: NORMAL AND PATHOLOGICAL

Abstract
The fine structure of normal, hyperplastic and adenomatous parathyroid glands of man have been described. Electron dense granules, similar to those described in man by Roth and Munger (1962) and identified as secretory material, have been described. However, before the definite significance of these granules can be defined, cytological studies must be more extensive and correlated with biochemical and fractionation analyses. These same granules have been described within the mitochondrial crista, and a fun?tional sequence has been postulated. Cytologically typical chief and oxyphil cells have been identified. On the basis of the number of mitochondria, many intermediate or transitional cells are described. It is postulated that there may be a single parenchymal cell type of the parathyroid glands of man which may be cytologically modified to represent varying physiological activities of the gland.