Neuropeptide Y Y1 receptor mRNA in rodent brain: distribution and colocalization with melanocortin-4 receptor

J Comp Neurol. 2005 Feb 14;482(3):217-43. doi: 10.1002/cne.20432.


The central neuropeptide Y (NPY) Y1 receptor (Y1-R) system has been implicated in feeding, endocrine, and autonomic regulation. In the present study, we systematically examined the brain distribution of Y1-R mRNA in rodents by using radioisotopic in situ hybridization histochemistry (ISHH) with a novel sensitive cRNA probe. Within the rat hypothalamus, Y1-R-specific hybridization was observed in the anteroventral periventricular, ventromedial preoptic, suprachiasmatic, paraventricular (PVH), dorsomedial, ventromedial, arcuate, and mamillary nuclei. In the rat, Y1-R mRNA expression was also seen in the subfornical organ, anterior hypothalamic area, dorsal hypothalamic area, and in the lateral hypothalamic area. In addition, Y1-R hybridization was evident in several extrahypothalamic forebrain and hindbrain sites involved in feeding and/or autonomic regulation in the rat. A similar distribution pattern of Y1-R mRNA was observed in the mouse brain. Moreover, by using a transgenic mouse line expressing green fluorescent protein under the control of the melanocortin-4 receptor (MC4-R) promoter, we observed Y1-R mRNA expression in MC4-R-positive cells in several brain sites such as the PVH and central nucleus of the amygdala. Additionally, dual-label ISHH demonstrated that hypophysiotropic PVH cells coexpress Y1-R and pro-thyrotropin-releasing hormone mRNAs in the rat. These observations are consistent with the proposed roles of the central NPY/Y1-R system in energy homeostasis.

Publication types

  • Comparative Study
  • Research Support, U.S. Gov't, P.H.S.

MeSH terms

  • Animals
  • Appetite Regulation / physiology
  • Brain Mapping*
  • Feeding Behavior / physiology
  • Hypothalamus / metabolism*
  • In Situ Hybridization, Fluorescence
  • Male
  • Mice
  • Mice, Transgenic
  • Prosencephalon / metabolism
  • RNA, Complementary / analysis
  • RNA, Messenger / metabolism*
  • Rats
  • Rats, Sprague-Dawley
  • Receptor, Melanocortin, Type 4 / metabolism*
  • Receptors, G-Protein-Coupled / genetics
  • Receptors, G-Protein-Coupled / metabolism*
  • Receptors, Neuropeptide / genetics
  • Receptors, Neuropeptide / metabolism*
  • Rhombencephalon
  • Tissue Distribution


  • Npy1r protein, rat
  • RNA, Complementary
  • RNA, Messenger
  • Receptor, Melanocortin, Type 4
  • Receptors, G-Protein-Coupled
  • Receptors, Neuropeptide