DEVELOPMENTAL NEUROSCIENCENovel expression of hypothalamic neuropeptide Y during postnatal development in the ratSinger, Lori K.1; Kuper, Joel1; Brogan, Rebecca S.1; Smith, M Susan1; Grove, Kevin L.1,2Author Information 1Division of Neuroscience, Oregon Regional Primate Research Center, Oregon Health Sciences University, 505 NW 185th Ave, Beaverton, OR 97006, USA 2Corresponding Author: Kevin L. Grove Acknowledgements: This work was supported by National Institutes of Health grants HD14643 and RR00163. J.K. was supported by a fellowship from the Murdock Foundation. The authors would like to thank Dr R.C. Speth for his review of this manuscript. Received 11 January 2000; accepted 27 January 2000 NeuroReport: April 7, 2000 - Volume 11 - Issue 5 - p 1075-1080 Buy Abstract Neuropeptide Y (NPY) is a potent orexigenic peptide. In the normal adult rat, hypothalamic NPY mRNA expression is limited to the arcuate nucleus (ARH). The purpose of this study was to characterize the developmental expression of NPY mRNA in the hypothalamus of the rat. In contrast to the normal adult rat, NPY mRNA was observed in the ARH, the dorsomedial hypothalamic nucleus (DMH) and the perifornical region (PFR) during development. NPY mRNA expression in all three regions increased progressively from postnatal days 0–4 (P0–4) to reach maximum levels at P16 and subsequently decreased to near adult levels by P30. The unique expression of NPY mRNA in the PFR and DMH may be important in establishing the proper management of energy homeostasis and body weight in the adult animal. © 2000 Lippincott Williams & Wilkins, Inc.