[Study on the cellular proliferation and endocrine activity of the parathyroid gland in hyperparathyroidism]

Flow cytometric DNA analysis was performed in 21 cases of primary hyperparathyroidism (19 adenomas in 19 cases and 5 glands with primary hyperplasia) and 24 glands with secondary hyperplasia. Tissue intact-PTH concentration was measured in another 41 glands with secondary hyperplasia. Glands with adenoma had a higher proliferative index than normal glands or glands with secondary hyperplasia. In the adenoma group, there was a negative correlation between proliferative index and age, an indicator of the tumorous nature of adenomas. Daily urinary calcium excretion in case of adenoma and tissue intact-PHT concentration in glands with secondary hyperplasia also showed correlations with proliferative index, which demonstrates a close relationship between cellular proliferation and endocrine activity. Gland weight and proliferative index had no significant correlation in both groups. Therefore, another mechanism besides cellular proliferation and endocrine activity, such as number of non-functional parathyroid cells, should be considered.