BEHAVIOURIntraparaventricular neuropeptide Y and ghrelin induce learned behaviors that report food deprivation in ratsJewett, David C.a; Lefever, Timothy W.a; Flashinski, Douglas P.a; Koffarnus, Mikhail N.a; Cameron, Constance R.a; Hehli, Daniel J.a; Grace, Martha K.b c d; Levine, Allen S.b c dAuthor Information aDepartment of Psychology, University of Wisconsin-Eau Claire, Eau Claire, Wisconsin bDepartment of Food Science and Nutrition, University of Minnesota, St Paul c VA Medical Center dMinnesota Obesity Center, Minneapolis, Minnesota, USA Correspondence and requests for reprints to David C. Jewett, PhD, Department of Psychology, University of Wisconsin-Eau Claire, Eau Claire, WI 54702, USA Tel: +1 715 836 2429; fax: +1 715 836 2214; e-mail: firstname.lastname@example.org Sponsorship: Research supported by University of Wisconsin-Eau Claire Center for Excellence in Faculty and Undergraduate Student Research Collaboration Grants, the Department of Veterans Affairs, and the Minnesota Obesity Center. Received 13 February 2006; accepted 14 February 2006 NeuroReport: May 15th, 2006 - Volume 17 - Issue 7 - p 733-737 doi: 10.1097/01.wnr.0000215767.94528.fb Buy SDC Metrics Abstract Rats were trained to discriminate between 2 and 22-h food deprivation in a choice paradigm. During tests, 20 min of food consumption eliminated internal stimuli associated with 22-h food deprivation. In other tests, rats food-restricted for 2 h were given neuropeptide Y or ghrelin by administration into the paraventricular nucleus of the hypothalamus. Both neurochemicals induced effects similar to those following 22-h food restriction (increased behavior appropriate for 22-h deprivation). These findings suggest that internal stimuli produced by 22-h food deprivation are altered by food consumption and mimicked by feeding-inducing neurochemicals administered into a brain area associated with feeding regulation. Thus, hunger discrimination is a useful model to examine neurochemical and dietary factors that alter internal states associated with eating. © 2006 Lippincott Williams & Wilkins, Inc.