Catalogo Articoli (Spogli Riviste)

OPAC HELP

Titolo:
TESTOSTERONE REGULATES GONADOTROPIN-RELEASING HORMONE-INDUCED CALCIUMSIGNALS IN MALE-RAT GONADOTROPHS
Autore:
TOBIN VA; CANNY BJ;
Indirizzi:
MONASH UNIV,DEPT PHYSIOL CLAYTON VIC 3168 AUSTRALIA MONASH UNIV,DEPT PHYSIOL CLAYTON VIC 3168 AUSTRALIA
Titolo Testata:
Endocrinology
fascicolo: 4, volume: 137, anno: 1996,
pagine: 1299 - 1305
SICI:
0013-7227(1996)137:4<1299:TRGHC>2.0.ZU;2-W
Fonte:
ISI
Lingua:
ENG
Soggetto:
STIMULATED PITUITARY GONADOTROPHS; MESSENGER-RNA LEVELS; LUTEINIZING-HORMONE; SECRETORY RESPONSES; CELLS; OSCILLATIONS; MOBILIZATION; LH; DIACYLGLYCEROL; PROGESTERONE;
Tipo documento:
Article
Natura:
Periodico
Settore Disciplinare:
Science Citation Index Expanded
Citazioni:
41
Recensione:
Indirizzi per estratti:
Citazione:
V.A. Tobin e B.J. Canny, "TESTOSTERONE REGULATES GONADOTROPIN-RELEASING HORMONE-INDUCED CALCIUMSIGNALS IN MALE-RAT GONADOTROPHS", Endocrinology, 137(4), 1996, pp. 1299-1305

Abstract

As the GnRH-induced secretion of gonadotropins is critically dependent upon an increase in the intracellular calcium ion concentration ([Ca2+](i)) and modulated by gonadal factors, the effects of gonadal steroids on the pattern of calcium mobilization in single gonadotrophs of the male rat were examined using the fluorescent Ca2+ indicator fura-2/AM. In cells from intact rats, low concentrations of GnRH induce repetitive oscillations in [Ca2+](i), whereas spike-plateau responses are observed at higher concentrations in single gonadotrophs. After castration, there was a significant change in the relationship between the GnRH concentration and the changes in [Ca2+](i). Increasing concentrations of GnRH (to 1 mu M) generate fewer spike-plateau responses in gonadotrophs from castrate rats, with oscillatory responses predominating. This change develops with time after castration, with the proportion of cells oscillating in response to 100 nM GnRH peaking by 7 days. Thiseffect of castration on GnRH-induced [Ca2+](i) signals was reversed by treatment with testosterone propionate (100 mu g/100 g BW . day). Castration-induced decreases in serum testosterone, seminal vesicle, andprostate weights and increases in serum LH concentration were also corrected by testosterone propionate treatment. These findings demonstrate that testosterone regulates GnRH-stimulated Ca2+ signals in gonadotrophs and suggest that gonadal steroids exert a regulatory role in thesecretion of gonadotropinss at the level of Ca2+ mobilization.

ASDD Area Sistemi Dipartimentali e Documentali, Università di Bologna, Catalogo delle riviste ed altri periodici
Documento generato il 28/09/20 alle ore 15:20:48