Prepro-orexin mRNA expression in the rat brain is increased during pregnancy

Neurosci Lett. 2004 Sep 16;368(1):73-7. doi: 10.1016/j.neulet.2004.06.068.

Abstract

The purpose of this study was to investigate whether orexin expression in the rat brain was changed during pregnancy. Brain samples were obtained from 5 nonpregnant rats and 10 pregnant rats (5; day 10 of gestation, and 5; day 20 of gestation). Reverse transcriptase-polymerase chain reaction (RT-PCR) analysis was performed to investigate the expression of prepro-orexin mRNA and the housekeeping gene in the rat brain. The signals were quantified by the densitometric analysis. The distribution and expression of orexin-A and orexin-B were determined using immunohistochemistry. The ratio of the prepro-orexin mRNA expressions to the housekeeping gene expression in pregnant rat brain were significantly higher than that in nonpregnant control. There was no significant difference between prepro-orexin mRNA levels of day 10 and day 20 of gestation. Immunohistochemical staining for orexin-A and orexin-B was present in neurons within and around the lateral and posterior hypothalamic areas in both nonpregnant and pregnant rats. These results suggest that increased prepro-orexin mRNA levels at early gestational age in the maternal rat has a role on energy metabolism during pregnancy.

MeSH terms

  • Actins / biosynthesis
  • Actins / genetics
  • Animals
  • Body Weight / drug effects
  • Brain Chemistry / physiology*
  • Female
  • Gene Expression Regulation / physiology
  • Hypothalamus / drug effects
  • Hypothalamus / metabolism
  • Intracellular Signaling Peptides and Proteins
  • Luteinizing Hormone / metabolism
  • Neuropeptides / biosynthesis*
  • Orexins
  • Pregnancy / metabolism*
  • Protein Precursors / biosynthesis*
  • RNA, Messenger / biosynthesis*
  • Rats
  • Rats, Wistar
  • Reverse Transcriptase Polymerase Chain Reaction

Substances

  • Actins
  • Intracellular Signaling Peptides and Proteins
  • Neuropeptides
  • Orexins
  • Protein Precursors
  • RNA, Messenger
  • Luteinizing Hormone