Fine structural features of secretion in adenomas of human pituitary gland.

Abstract

Ultrastructural investigation of 274 human pituitary adenomas and 39 nontumorous adenohypophyses revealed two distinct types of secretion. Exocytosis was characteristic of prolactin cell adenomas, mixed growth hormone-prolactin cell adenomas, acidophil stem cell adenomas, and nontumorous prolactin cells. The second type, termed "transmembrane effusion," was noted in corticotroph, thyrotroph, gonadotroph, undifferentiated cell adenomas, and oncocytomas, as well as nontumorous corticotrophs, thyrotrophs, and gonadotrophs. It differed from that of prolactin cells and resembled diacrine secretion of gastrointestinal gastrin cells and membrane release in the neurohypophysis. In adenomatous and nontumorous growth hormone cells, neither exocytosis nor transmembrane effusion were apparent, hence a third type of release is suggested. Electron microscopic study of release mechanisms is helpful in the differential diagnosis of pituitary adenomas, since discharge of secretory products is not identical in the various tumor types.

• Authors: D R Ryder, E Horvath, K Kovacs
• Journal: Archives of pathology & laboratory medicine (Arch Pathol Lab Med) Vol. 104 Issue 10 Pg. 518-22 (Oct 1980) ISSN: 0003-9985 [Print] United States
• PMID: 6774693 (Publication Type: Journal Article)

Chemical References

• Gonadotropin-Releasing Hormone
• Thyrotropin-Releasing Hormone
• Follicle Stimulating Hormone
• Thyrotropin
• Growth Hormone

Topics

• Adenoma (metabolism, ultrastructure)
• Exocytosis
• Female
• Follicle Stimulating Hormone (metabolism)
• Gonadotropin-Releasing Hormone (metabolism)
• Growth Hormone (metabolism)
• Humans
• Male
• Pituitary Gland (metabolism, ultrastructure)
• Pituitary Neoplasms (metabolism, ultrastructure)
• Thyrotropin (metabolism)
• Thyrotropin-Releasing Hormone (metabolism)