Catalogo Articoli (Spogli Riviste)

OPAC HELP

Titolo:
Gonadotropins, their receptors, and the regulation of testicular functionsin fish
Autore:
Schulz, RW; Vischer, HF; Cavaco, JEB; Santos, EM; Tyler, CR; Goos, HJT; Bogerd, J;
Indirizzi:
Univ Utrecht, Fac Biol, Dept Dev Biol, Res Grp Endocrinol, NL-3584 CH Utrecht, Netherlands Univ Utrecht Utrecht Netherlands NL-3584 CH 3584 CH Utrecht, Netherlands Brunel Univ, Dept Biol Sci, Uxbridge UB8 3PA, Middx, England Brunel Univ Uxbridge Middx England UB8 3PA bridge UB8 3PA, Middx, England
Titolo Testata:
COMPARATIVE BIOCHEMISTRY AND PHYSIOLOGY B-BIOCHEMISTRY & MOLECULAR BIOLOGY
fascicolo: 2-3, volume: 129, anno: 2001,
pagine: 407 - 417
SICI:
1096-4959(200106)129:2-3<407:GTRATR>2.0.ZU;2-Q
Fonte:
ISI
Lingua:
ENG
Soggetto:
CATFISH CLARIAS-GARIEPINUS; FOLLICLE-STIMULATING-HORMONE; EEL ANGUILLA-JAPONICA; MESSENGER-RNA LEVELS; MALE AFRICAN CATFISH; II-BETA-SUBUNIT; SALMON ONCORHYNCHUS-RHODURUS; NUCLEAR ANDROGEN RECEPTORS; FIBROBLAST GROWTH-FACTOR; RIBONUCLEIC-ACID LEVELS;
Keywords:
teleost fish; African catfish; luteinizing hormone; follicle-stimulating hormone; luteinizing hormone receptor; follicle-stimulating hormone receptor; androgen production; spermatogenesis; steroid feedback;
Tipo documento:
Article
Natura:
Periodico
Settore Disciplinare:
Life Sciences
Citazioni:
72
Recensione:
Indirizzi per estratti:
Indirizzo: Schulz, RW Univ Utrecht, Fac Biol, Dept Dev Biol, Res Grp Endocrinol, Padualaan 8, NL-3584 CH Utrecht, Netherlands Univ Utrecht Padualaan 8 Utrecht Netherlands NL-3584 CH rlands
Citazione:
R.W. Schulz et al., "Gonadotropins, their receptors, and the regulation of testicular functionsin fish", COMP BIOC B, 129(2-3), 2001, pp. 407-417

Abstract

The pituitary gonadotropins luteinizing hormone (LH) and follicle-stimulating hormone (FSH) regulate steroidogenesis and spermatogenesis by activating receptors expressed by Leydig cells (LH receptor) and Sertoli cells (FSH receptor), respectively. This concept is also valid in fish, although the piscine receptors may be less discriminatory than their mammalian counterparts. The main biological activity of LH is to regulate Leydig-cell steroid production. Steroidogenesis is moreover modulated in an autoregulatory manner by androgens, The male sex steroids (testosterone in higher vertebrates, 11-ketotestosterone in fish) are required for spermatogenesis, but their mode of action has remained obscure. While piscine FSH also appears to have steroidogenic activity, specific roles have not been described yet in the testis. The feedback of androgens on gonadotrophs presents a complex pattern. Aromatizable androgens/estrogens stimulate LH synthesis in juvenile fish; this effect fades out during maturation. This positive feedback on LH synthesis is balanced by a negative feedback on LH release, which may involve GnRH neurones. While the role of GnRH as LH secretagogue is evident, we have found no indication in adult male African catfish for a direct, GnRH-mediated stimulation of LH synthesis. The limited available information at present precludes a generalized view on the testicular feedback on FSH. (C) 2001 Elsevier Science Inc. All rights reserved.

ASDD Area Sistemi Dipartimentali e Documentali, Università di Bologna, Catalogo delle riviste ed altri periodici
Documento generato il 29/03/20 alle ore 23:44:55