Journal of Clinical Endocrinology & Metabolism, Vol 68, 1128-1135, Copyright © 1989 by Endocrine Society

ARTICLES

Gonadotropin release by clinically nonfunctioning and gonadotroph pituitary adenomas in vivo and in vitro: relation to sex and effects of thyrotropin-releasing hormone, gonadotropin-releasing hormone, and bromocriptine

DJ Kwekkeboom, FH de Jong and SW Lamberts
Department of Medicine, University Hospital Dijkzigt, Rotterdam, The Netherlands.

We studied in vivo hormone levels and in vitro hormone and subunit release in a group of 22 patients who were operated upon because of a clinically nonfunctioning or gonadotroph pituitary adenoma. In vivo, 5 of the 22 patients, all men, had hypersecretion of FSH, LH beta, or alpha-subunit. An elevated ratio of serum alpha-subunit to LH and FSH was found in 6 of 8 women in vivo, although in all 6 women serum LH, FSH, and alpha-subunit levels were low. LH, FSH, alpha-subunit, LH beta, or a combination of these glycoprotein hormones could be demonstrated in 19 of 22 cultured adenomas. We conclude that 1) virtually all clinically nonfunctioning adenomas contain or release gonadotropins or their subunits in vitro; 2) in vivo hypersecretion of these hormones and subunits occurs infrequently, and in this series only in men; 3) an elevated ratio of alpha-subunit to LH and FSH is frequently found in women and may prove to be a useful diagnostic tool; 4) responses to TRH and bromocriptine do not depend on baseline gonadotropin levels, either in vitro or in vivo, implying that the distinction between gonadotroph adenomas and adenomas without hypersecretion of gonadotropins in vivo is absent where hormone dynamics are concerned.

This article has been cited by other articles:

				P L Hanson, S J B Aylwin, J P Monson, and J M Burrin FSH secretion predominates in vivo and in vitro in patients with non-functioning pituitary adenomas Eur. J. Endocrinol., March 1, 2005; 152(3): 363 - 370. [Abstract] [Full Text] [PDF]

				M. J. Välimäki, A. Tiitinen, H. Alfthan, A. Paetau, A. Poranen, T. Sane, and U.-H. Stenman Ovarian Hyperstimulation Caused by Gonadotroph Adenoma Secreting Follicle-Stimulating Hormone in 28-Year-Old Woman J. Clin. Endocrinol. Metab., November 1, 1999; 84(11): 4204 - 4208. [Abstract] [Full Text]

				N. Sanno, L. Jin, X. Qian, R. Y. Osamura, B. W. Scheithauer, K. Kovacs, and R. V. Lloyd Gonadotropin-Releasing Hormone and Gonadotropin-Releasing Hormone Receptor Messenger Ribonucleic Acids Expression in Nontumorous and Neoplastic Pituitaries J. Clin. Endocrinol. Metab., June 1, 1997; 82(6): 1974 - 1982. [Abstract] [Full Text] [PDF]

				P. Chanson, J. Pantel, J. Young, B. Couzinet, J.-M. Bidart, and G. Schaison Free Luteinizing-Hormone Beta-Subunit in Normal Subjects and Patients with Pituitary Adenomas J. Clin. Endocrinol. Metab., May 1, 1997; 82(5): 1397 - 1402. [Abstract] [Full Text] [PDF]