Peptide YY containing enteroendocrine cells and peripheral tissue sensitivity to PYY and PYY(3-36) are maintained in diet-induced obese and diet-resistant rats

Institute of Infection, Immunity and Inflammation and Hotchkiss Brain Institute, Department of Physiology and Biophysics, Faculty of Medicine, University of Calgary, Calgary, Alta., Canada.
Peptides (Impact Factor: 2.62). 07/2007; 28(6):1185-90. DOI: 10.1016/j.peptides.2007.03.011
Source: PubMed


Peptide YY (PYY) is a gastrointestinal hormone, localized in enteroendocrine L-cells. Its hydrolyzed form PYY(3-36) is a satiety factor. The aim of this study was to identify if intestinal PYY enteroendocrine cells or content correlate with the diet-induced obese (DIO) or diet-resistant (DR) phenotypes. We also examined intestinal sensitivity to PYY and PYY(3-36) in DIO and DR rats. Animals were maintained on a medium-high fat diet and split into DIO and DR groups based on weight gain. PYY immunoreactive cells were unaltered in DIO intestine and stomach compared to DR rats. PYY content and circulating levels were also unchanged in DIO rats. Intestinal PYY and PYY(3-36) responses were enhanced in fasted rats, and equipotent in both DIO and DR jejunum. We conclude that PYY cell number, tissue content and peripheral sensitivity are maintained in DIO rats. Our data suggests that neither PYY nor PYY(3-36) contribute to the maintenance of either the DIO or DR phenotype, and that peripheral resistance to PYY and PYY(3-36) does not accompany DIO.

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    • "Animals that were of intermediate weights (600–700 g) were eliminated from this study as they could not be reliably classified as DR or DIO rats. The DIO and DR phenotypes were validated in accordance with the DIO model of others (Levin and Dunn-Meynell, 2002; Hyland et al., 2007; Li et al., 2011) and in our own colony (Smith and Ferguson, 2012). "
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