Your browser doesn't support javascript.
loading
Secretory Patterns of Leptin and Luteinizing Hormone in Food-Restricted Young Female Sheep
Recabarren, Sergio E; Lobos, Alejandro; Torres, Veronica; Oyarzo, Roberto; Sir-Petermann, Teresa.
  • Recabarren, Sergio E; Universidad de Concepción. Faculty of Veterinary Medicine. Laboratory of Animal Physiology and Endocrinology. CL
  • Lobos, Alejandro; Universidad de Concepción. Faculty of Veterinary Medicine. Laboratory of Animal Physiology and Endocrinology. CL
  • Torres, Veronica; Universidad de Concepción. Faculty of Veterinary Medicine. Laboratory of Animal Physiology and Endocrinology. CL
  • Oyarzo, Roberto; Universidad de Concepción. Faculty of Veterinary Medicine. Laboratory of Animal Physiology and Endocrinology. CL
  • Sir-Petermann, Teresa; Universidad de Chile. Faculty of Medicine. Department of Internal Medicine. Laboratory of Endocrinology and Metabolism. Santiago. CL
Biol. Res ; 37(3): 371-384, 2004. tab, graf
Artigo em Inglês | LILACS | ID: lil-394432
RESUMO
Leptin, the product of the ob gene, has been proposed as a metabolic signal that regulates the secretion of GnRH/LH. This may be critical during prepubertal development to synchronize information about energy stores and the secretion of GnRH/LH. This study aimed to assess the effect of food restriction on the episodic secretion of leptin and LH in young female sheep. Five 20-week-old prepubertal females were fed a low-level diet for 10 weeks to maintain the body weight. Control females of the same age received food ad libitum. Blood samples were collected at 10-min intervals for six hours at 20, 26, and 30 weeks of age, and plasma leptin, LH, insulin and cortisol concentrations were measured. In the control group, no changes were found in pulsatile LH secretion characteristics. Mean LH concentrations and LH amplitude were lower in the food-restricted group than in the control group at 26 and 30 weeks of age. In the control group, pulsatile leptin secretion did not change. When compared to control lambs of the same age, the food-restricted group showed lower mean plasma leptin concentrations, pulse amplitude and plasma insulin levels, after 6 weeks of restriction (week 26), although by week 30, plasma leptin concentrations and plasma insulin rose to those of the control group. Leptin pulse frequency did not change, nor did mean plasma levels of insulin in the control group at any age studied. Mean plasma concentration of cortisol did not change within or between groups. These data suggest that plasma leptin concentrations may not be associated with the onset of puberty under regular feeding and natural photoperiod in lambs. Prolonged food restriction, however, induces metabolic adaptations that allow an increase of leptin during the final period, probably related to the development of some degree of insulin resistance..
Assuntos
Texto completo: DisponíveL Índice: LILACS (Américas) Assunto principal: Ovinos / Hormônio Luteinizante / Leptina / Privação de Alimentos Limite: Animais Idioma: Inglês Revista: Biol. Res Assunto da revista: Biologia Ano de publicação: 2004 Tipo de documento: Artigo / Documento de projeto País de afiliação: Chile Instituição/País de afiliação: Universidad de Chile/CL / Universidad de Concepción/CL

Similares

MEDLINE

...
LILACS

LIS

Texto completo: DisponíveL Índice: LILACS (Américas) Assunto principal: Ovinos / Hormônio Luteinizante / Leptina / Privação de Alimentos Limite: Animais Idioma: Inglês Revista: Biol. Res Assunto da revista: Biologia Ano de publicação: 2004 Tipo de documento: Artigo / Documento de projeto País de afiliação: Chile Instituição/País de afiliação: Universidad de Chile/CL / Universidad de Concepción/CL