HOME HELP FEEDBACK SUBSCRIPTIONS ARCHIVE SEARCH TABLE OF CONTENTS		QUICK SEARCH:   [advanced] Author: Keyword(s): Year:  Vol:  Page:

This Article Full Text Full Text (PDF) All Versions of this Article: 295/1/R51    most recent 00234.2007v1 Alert me when this article is cited Alert me if a correction is posted Citation Map Services Email this article to a friend Similar articles in this journal Similar articles in PubMed Alert me to new issues of the journal Download to citation manager Citing Articles Citing Articles via HighWire Citing Articles via Web of Science (2) Citing Articles via Google Scholar Google Scholar Articles by Unniappan, S. Articles by Kieffer, T. J. Search for Related Content PubMed PubMed Citation Articles by Unniappan, S. Articles by Kieffer, T. J.

CALL FOR PAPERS
Neural Integration of Peripheral Signals Implicated in the Control of Energy Homeostasis and Metabolism

Leptin extends the anorectic effects of chronic PYY(3-36) administration in ad libitum-fed rats

Laboratory of Molecular and Cellular Medicine, Departments of Cellular and Physiological Sciences and Surgery, Life Sciences Institute, University of British Columbia, Vancouver, Canada

Submitted 6 April 2007 ; accepted in final form 14 April 2008

Acute administration of peptide YY(3-36) [PYY(3-36)] results in a reduction in food intake in several different vertebrates. However, long-term continuous administration of PYY(3-36) causes only a transient reduction in food intake, thus potentially limiting its therapeutic efficacy. We hypothesized that a fall in leptin levels associated with reduced food intake could contribute to the transient anorectic effects of continuous PYY(3-36) infusion and thus that leptin replacement might prolong the anorectic effects of PYY(3-36). Seven-day administration of 100 µg·kg body wt^–1·day^–1 PYY(3-36) using osmotic minipumps caused a significant reduction in food intake of ad libitum-fed rats, but only for the first 2 days postimplantation. Circulating levels of leptin were reduced 1 day following continuous infusion of PYY(3-36), and combined leptin infusion at a dose of leptin that had no anorectic effects on its own (100 µg·kg body wt^–1·day^–1) prolonged the anorectic actions of PYY(3-36) in ad libitum-fed rats for up to 6 days postimplantation and yielded reduced weight gain compared with either peptide alone. The inhibitory effects of 100 µg·kg body wt^–1·day^–1 PYY(3-36) on food intake were absent in rats refed after a 24-h fast and substantially reduced at a dose of 1,000 µg·kg body wt^–1·day^–1 PYY(3-36). Leptin replacement was unable to recover the anorectic effects of PYY(3-36) in fasted rats. Our results suggest that an acute fall in leptin levels is not solely responsible for limiting duration of action of chronic PYY(3-36) infusion, yet chronic coadministration of a subanorectic dose of leptin can extend the anorectic effects of PYY(3-36).

obesity; food intake; osmotic minipumps; body weight; hormones

This article has been cited by other articles:

				E. Karra, K. Chandarana, and R. L. Batterham The role of peptide YY in appetite regulation and obesity J. Physiol., January 1, 2009; 587(1): 19 - 25. [Abstract] [Full Text] [PDF]

				R. D. Reidelberger, A. C. Haver, P. K. Chelikani, and J. L. Buescher Effects of different intermittent peptide YY (3-36) dosing strategies on food intake, body weight, and adiposity in diet-induced obese rats Am J Physiol Regulatory Integrative Comp Physiol, August 1, 2008; 295(2): R449 - R458. [Abstract] [Full Text] [PDF]