epithelial cell of parathyroid gland transitional cell of parathyroid gland 2010-09-08T02:33:50Z One of three types of epithelial cells that populate the parathyroid gland; cytological characteristics intermediate between those of the chief cell and of the oxyphil cell. Because only one hormone is produced, the three cell forms are widely believed to be different phases in the life cycle of a single cell type, with the chief cell being its physiologically active stage. FMA:69324