title: Impact of changes in postnatal nutrition on puberty onset and the expression of hypothalamic GnRH and ghrelin.
abstract: OBJECTIVE
  Ghrelin is an octanoylated peptide hormone with multiple and diverse physiologic functions including an important role in energy homeostasis and reproduction. In this study, the adjustment effects of different postnatal nutritional status on puberty onset and the expression of hypothalamic ghrelin and gonadotrophin-releasing hormone (GnRH) were examined in 1 day-old female Sprague-Dawley rats.
  
  
  METHODS
  Animals were randomly assigned into four groups: overnutrition group (Group O), normal group (Group N, control group), and undernutrition groups (Group U and U2). Western blot analysis and immunohistochemistry were used to analyze the expression of hypothalamic ghrelin and GnRH.
  
  
  RESULTS
  With a low level expression of hypothalamic ghrelin, the appearance of puberty onset and secretion peak of GnRH in Group O was earlier than the other groups.
  
  
  CONCLUSIONS
  Undernutrition delayed puberty onset and the GnRH peak, at the same time, promoted the expression of hypothalamic ghrelin.While, the expression of hypothalamic ghrelin was suppressed at puberty onset.
authors.affiliation: Department of Endocrinology, Shanghai Children's Hospital, Shanghai Jiao Tong University, Shanghai, China. lipin21@126.com  
authors.forename: L-L
authors.initials: LL
authors.lastname: Cui
authors.forename: P
authors.initials: P
authors.lastname: Li
authors.forename: Z-Y
authors.initials: ZY
authors.lastname: Zhu
mesh_terms: D000818:Animals; D000831:Animals, Newborn; D005260:Female; D005786:Gene Expression Regulation; D054439:Ghrelin / Q000096:biosynthesis*; D007987:Gonadotropin-Releasing Hormone / Q000096:biosynthesis*; D006062:Gonadotropins / Q000378:metabolism; D007031:Hypothalamus / Q000378:metabolism*; D044342:Malnutrition / Q000378:metabolism; D009752:Nutritional Status / Q000502:physiology*; D051381:Rats; D017207:Rats, Sprague-Dawley; D012741:Sexual Maturation / Q000502:physiology*
chemical_list: D054439:Ghrelin; D006062:Gonadotropins; D007987:Gonadotropin-Releasing Hormone