title: Developmental changes in the responsiveness of hypothalamic ER alpha mRNA levels to food deprivation.
abstract: OBJECTIVE
  Estrogen plays an important role in feeding and energy balance, and the critical role of estrogen in the control of appetite and energy balance is mediated by hypothalamic estrogen receptor (ER) alpha. In undernourished rodents, hypothalamic ER alpha mRNA expression are decreased. Responses of some hypothalamic factors to negative energy balance develop during the early neonatal period.
  
  
  METHODS
  In this study, we examined the developmental changes of fasting-induced alterations in hypothalamic ER alpha mRNA expression in female rats.
  
  
  RESULTS
  ER alpha mRNA expression was reduced after a 12-h or 24-h fast at postnatal days 15 and 25, but not at day 5. Serum estradiol levels in postnatal day 25 rats were not changed by fasting. Although serum leptin levels were suppressed by fasting at all ages, hypothalamic ER alpha mRNA expression at postnatal day 25 was not changed by leptin administration after a 24-h fast.
  
  
  CONCLUSIONS
  These data show that the sensitivity of hypothalamic ER alpha to negative energy balance may not be established in the early neonatal period, and that it develops by postnatal day 15. Decreased leptin levels might not be involved in the alterations of hypothalamic ER alpha mRNA expression in the undernourished condition.
authors.affiliation: Department of Obstetrics and Gynecology, The University of Tokushima Graduate School, Institute of Health Biosciences, 3-18-15 Kuramoto-Cho, Tokushima 770-8503, Japan. iwasa.takeshi@tokushima-u.ac.jp.
authors.forename: Takeshi
authors.initials: T
authors.lastname: Iwasa
authors.affiliation: Department of Obstetrics and Gynecology, The University of Tokushima Graduate School, Institute of Health Biosciences, 3-18-15 Kuramoto-Cho, Tokushima 770-8503, Japan.
authors.forename: Toshiya
authors.initials: T
authors.lastname: Matsuzaki
authors.affiliation: Department of Obstetrics and Gynecology, The University of Tokushima Graduate School, Institute of Health Biosciences, 3-18-15 Kuramoto-Cho, Tokushima 770-8503, Japan.
authors.forename: Riyo
authors.initials: R
authors.lastname: Kinouchi
authors.affiliation: Department of Obstetrics and Gynecology, The University of Tokushima Graduate School, Institute of Health Biosciences, 3-18-15 Kuramoto-Cho, Tokushima 770-8503, Japan.
authors.forename: Ganbat
authors.initials: G
authors.lastname: Gereltsetseg
authors.affiliation: Department of Obstetrics and Gynecology, The University of Tokushima Graduate School, Institute of Health Biosciences, 3-18-15 Kuramoto-Cho, Tokushima 770-8503, Japan.
authors.forename: Masahiro
authors.initials: M
authors.lastname: Murakami
authors.affiliation: Department of Obstetrics and Gynecology, The University of Tokushima Graduate School, Institute of Health Biosciences, 3-18-15 Kuramoto-Cho, Tokushima 770-8503, Japan.
authors.forename: Akira
authors.initials: A
authors.lastname: Kuwahara
authors.affiliation: Department of Obstetrics and Gynecology, The University of Tokushima Graduate School, Institute of Health Biosciences, 3-18-15 Kuramoto-Cho, Tokushima 770-8503, Japan.
authors.forename: Toshiyuki
authors.initials: T
authors.lastname: Yasui
authors.affiliation: Department of Obstetrics and Gynecology, The University of Tokushima Graduate School, Institute of Health Biosciences, 3-18-15 Kuramoto-Cho, Tokushima 770-8503, Japan.
authors.forename: Minoru
authors.initials: M
authors.lastname: Irahara
mesh_terms: D000367:Age Factors; D000818:Animals; D000831:Animals, Newborn; D001835:Body Weight / Q000502:physiology; D004734:Energy Metabolism / Q000502:physiology*; D047628:Estrogen Receptor alpha / Q000097:blood* / Q000235:genetics*; D005260:Female; D005508:Food Deprivation / Q000502:physiology*; D007031:Hypothalamus / Q000254:growth & development* / Q000502:physiology*; D020738:Leptin / Q000097:blood / Q000494:pharmacology; D011247:Pregnancy; D012333:RNA, Messenger / Q000378:metabolism; D051381:Rats
chemical_list: D047628:Estrogen Receptor alpha; D020738:Leptin; D012333:RNA, Messenger