Abstract
The Parathyroids were dissected out from 71 autopsy cases, fixed in 10% formalin, embedded in paraffin, sliced to a thickness of 6 microns and stained with Haematoxylin-Eosin. Photomicrograms of 50 fold magnification were used to calculate the relative areas of fatty infiltration and oxyphil cell islands, while a 400 fold magnification was used to estimate the total nuclear area (TNA) and total number of nuclei (TNN) in a unit area occupied entirely of chief cells, and also the average nuclear area (ANA) which may be obtained by dividing TNA by TNN. Twenty-five of the 71 cases had renal insufficiency as the main disease process leading to the fatal outcome, while the other 46, who died from various other causes, were used to calculate the correlation between age and histometrical values of the parathyroids. Above the age of 60, a marked increase in fatty infiltration and oxyphil islands was observed. TNA and ANA were found to decrease with advancing age showing a significant negative correlation, whereas TNN failed to show a significant correlation, indicating a decrease in size of individual nuclei, although the size of the cell as a whole did not change significantly. In renal disease, on the other hand, hyperplasia of each cell seemed to take place. Cases with aortic atherosclerosis showed changes similar to those caused by aging. TNA, TNN, and ANA also showed a significant negative correlation with systolic and diastolic blood pressure, suggesting that a decrease in size of individual nuclei and hyperplasia of each chief cell occurs as the blood pressure is elevated. These results might suggest some relationship between the function of the parathyroid gland and the aging process, especially the elevation of blood pressure and development of atherosclerosis.
