Catalogo Articoli (Spogli Riviste)

OPAC HELP

Titolo:
The sexually dimorphic expression of androgen receptors in the song nucleus hyperstriatalis ventrale pars caudale of the zebra finch develops independently of gonadal steroids
Autore:
Gahr, M; Metzdorf, R;
Indirizzi:
Max Planck Inst Behav Physiol, D-82319 Seewiesen, Germany Max Planck Inst Behav Physiol Seewiesen Germany D-82319 ewiesen, Germany
Titolo Testata:
JOURNAL OF NEUROSCIENCE
fascicolo: 7, volume: 19, anno: 1999,
pagine: 2628 - 2636
SICI:
0270-6474(19990401)19:7<2628:TSDEOA>2.0.ZU;2-N
Fonte:
ISI
Lingua:
ENG
Soggetto:
MESSENGER-RIBONUCLEIC-ACID; EARLY ESTROGEN-TREATMENT; SEX-DIFFERENTIATION; AROMATASE-ACTIVITY; GENETIC-CONTROL; RAT-BRAIN; BEHAVIOR; NEURONS; SYSTEM; FEMALE;
Keywords:
sexual dimorphism; androgens; estrogens; zebra finch; vocal control areas; HVc;
Tipo documento:
Article
Natura:
Periodico
Settore Disciplinare:
Life Sciences
Citazioni:
56
Recensione:
Indirizzi per estratti:
Indirizzo: Gahr, M FreeHVniv Amsterdam, Fac Biol, Dept Dev Neurobiol, Boolelaan 1087,NL-1081 Free Univ Amsterdam Boolelaan 1087 Amsterdam Netherlands NL-1081 HV
Citazione:
M. Gahr e R. Metzdorf, "The sexually dimorphic expression of androgen receptors in the song nucleus hyperstriatalis ventrale pars caudale of the zebra finch develops independently of gonadal steroids", J NEUROSC, 19(7), 1999, pp. 2628-2636

Abstract

The development of sex differences in brain structure and brain chemistry ("brain sex") of vertebrates is frequently thought to depend entirely on gonadal steroids such as androgens and estrogens, which act on the brain at the genomic level by binding to intracellular transcription factors, the androgen receptors (ARs) and estrogen receptors (ERs). These hormone actions are thought to shift the brain from a monomorphic to a dimorphic phenotype. One prominent such example is the nucleus hyperstriatalis ventrale pars caudale (HVc) of the zebra finch (Poephila guttata), a set of cells in the caudal forebrain involved in the control of singing. In contrast with previousstudies using nonspecific cell staining techniques, the size and neuron number of the HVc measured by the distribution of AR mRNA is already sexuallydimorphic on posthatching day (P)9. No ARs or ERs are expressed in the HVcbefore day 9. Slice cultures of the caudal forebrain of P5 animals show that the sexually dimorphic expression of AR mRNA in HVc is independent of the direct action of steroids on this nucleus or any of its immediate presynaptic or postsynaptic partners. Therefore, gonadal steroids do not appear tobe directly involved in the initial sex difference in the expression pattern of AR mRNA, size, and neuron number of the HVc. Furthermore, we demonstrate that the initial steroid-independent size and its subsequent steroid-independent growth by extension linearly with the extension of the forebrain explains 60-70% of the masculine development of the HVc. Thus, we suggest that epigenetic factors such as the gonadal steroids modify but cannot overwrite the sex difference in HVc volume determined autonomously in the brain.

ASDD Area Sistemi Dipartimentali e Documentali, Università di Bologna, Catalogo delle riviste ed altri periodici
Documento generato il 26/11/20 alle ore 20:29:55