The effect of thyrotropin-releasing hormone on gonadotropin and free alpha-subunit secretion in patients with acromegaly and functionless pituitary tumors.
Thyroid
; 8(10): 935-9, 1998 Oct.
Article
em En
| MEDLINE
| ID: mdl-9827662
ABSTRACT
UNLABELLED Paradoxical response of luteinizing hormone (LH), follicle-stimulating hormone (FSH), and alpha-subunits (alpha-SU) to thyrotropin-releasing hormone (TRH) have previously been reported in individuals with clinically nonfunctioning pituitary tumors (NFT). In the present study, we assessed the in vivo responses of LH, FSH, alpha-SU to TRH in 34 patients with NFT and 29 patients with agromegaly. Twenty-three clinically NFT were postoperatively analyzed by immunocytochemistry and 21 stained positive for beta-FSH and/or beta-LH. Two patients with NFT had elevated basal circulating levels of FSH (41.5 IU/L) and thus were characterized as FSH-secreting adenomas. TRH in these patients increased LH from basal 1.6 IU/L to 32.6 IU/L. In other patients with NFT, circulating levels of glycoprotein peptides were not elevated. TRH induced significant rise of LH in 8 (23.5%), FSH in 5 (14.7%), and alpha-SU in 10 (29.4%) patients with NFT. Thus, a bolus dose of TRH elicited a notable increment in FSH, LH or alpha-SU in 23 of 34 patients with NFT. Among 29 patients with acromegaly, LH rose in 6 (20.7%), FSH in 5 (17.2%), and alpha-SU in 3 (10.3%) patients. IN CONCLUSION:
(1) We confirm that most NFTs are capable of synthesizing gonadotropin hormones and subunits (beta-FSH, beta-LH). (2) Most patients in our study responded by either FSH, LH or alpha-SU secretion after TRH, independent of basal hormone levels. Furthermore, recent studies show that by measurement of TRH stimulated beta-FSH and beta-LH one might further improve the diagnostic tools. (3) Gonadotropin response and possibly alpha-SU to TRH are also found in some patients with acromegaly. This could be a marker of a plurihormonal pituitary tumor.
Buscar no Google
Coleções:
01-internacional
Base de dados:
MEDLINE
Assunto principal:
Neoplasias Hipofisárias
/
Acromegalia
/
Subunidade alfa de Hormônios Glicoproteicos
/
Adenoma
/
Hormônio Liberador de Tireotropina
/
Gonadotropinas Hipofisárias
Limite:
Adolescent
/
Adult
/
Aged
/
Female
/
Humans
/
Male
/
Middle aged
Idioma:
En
Revista:
Thyroid
Assunto da revista:
ENDOCRINOLOGIA
Ano de publicação:
1998
Tipo de documento:
Article
País de afiliação:
Iugoslávia