Induction of members of the Fos/Jun family of immediate-early genes in identified hypothalamic neurons: in vivo evidence for differential regulation

Neuroscience. 1996 Jul;73(2):473-85. doi: 10.1016/0306-4522(96)00076-0.


In situ hybridization was used to measure the expression of members of the Fos/Jun family of immediate-early genes in hypothalamic neurons in vivo following defined stimuli that utilize different afferent pathways. Only c-jun messenger RNA was expressed in the hypothalamic supraoptic and paraventricular nuclei of control animals. Intravenous infusions of sodium chloride solutions of different tonicity produced a range of plasma osmolalities within physiological limits. While the induction of c-fos and jun B messenger RNAs followed the stimulus intensity, the expression of c-jun was repressed at low levels of stimulation. A higher level of osmotic stimulation was able to co-induce c-jun with the c-fos, jun B and fos B genes, suggesting that other signalling pathways may then be activated. Parturition or systemic administration of cholecystokinin, that activate supraoptic and paraventricular neurons via ascending afferent pathways from the brainstem, both induced c-fos, but not the other genes, in the magnocellular nuclei. Use of double in situ hybridization confirmed that, unlike with osmotic stimulation, induction of c-fos only occurred in oxytocin neurons. These two stimuli did not cause a concomitant repression of c-jun messenger RNA expression in magnocellular oxytocin neurons. These patterns of induction provide evidence for the differential regulation of members of this family of genes in a physiological context.

Publication types

  • Research Support, Non-U.S. Gov't

MeSH terms

  • Animals
  • Antisense Elements (Genetics)
  • Cholecystokinin / pharmacology
  • Female
  • Gene Expression Regulation / drug effects
  • Genes, Immediate-Early*
  • Genes, fos*
  • Genes, jun*
  • Hypothalamus / metabolism*
  • In Situ Hybridization
  • Infusions, Intravenous
  • Male
  • Multigene Family
  • Neurons / metabolism*
  • Organ Specificity
  • Osmolar Concentration
  • Paraventricular Hypothalamic Nucleus / metabolism
  • Proto-Oncogene Proteins c-fos / biosynthesis
  • Proto-Oncogene Proteins c-jun / biosynthesis
  • RNA, Messenger / biosynthesis
  • Rats
  • Rats, Wistar
  • Sodium Chloride / administration & dosage
  • Sodium Chloride / pharmacology
  • Supraoptic Nucleus / metabolism
  • Transcription, Genetic*


  • Antisense Elements (Genetics)
  • Proto-Oncogene Proteins c-fos
  • Proto-Oncogene Proteins c-jun
  • RNA, Messenger
  • Sodium Chloride
  • Cholecystokinin