Formation of Centrioles in Some Endocrine Adenomas

Abstract

Centrioles, known to play a fundamental role in mitotic division, are regarded as representing self-replicating organelles. They occur with varying frequency in different normal cells and exhibit uniform appearances showing no signs indicative of duplication such as budding or division. In order to obtain a deeper insight into centriole formation and evolution, cases of parathyroid and pituitary adenomas with a high centriole population were investigated by electron microscopy.The material used for the present study consisted of 4 chief cell adenomas of the parathyroid gland, 7 sparsely granulated pituitary growth hormone cell adenomas and 1 mixed cell pituitary adenoma composed of sparsely granulated growth hormone cells and prolactin cells. These adenomas were selected from a large number of cases (26 parathyroid adenomas and 49 pituitary adenomas). All specimens were obtained by surgery from various patients with hyperparathyroidism or acromegaly. Small pieces of tissue were fixed immediately after removal in 2.5 per cent glutaraldehyde in Sorensen's buffer, postfixed in 1 per cent osmium tetroxide in Millonig's buffer, dehydrated in graded ethanol and embedded in Epon 812.