Increases in sucrose consumption, but not ethanol consumption, following ICVNPY administration

Neuropeptide Y (NPY) is a centrally acting neuromodulator that influences b oth consummatory behaviors and anxiety. NPY's effects on feeding are primar ily regulated through Y5 receptors in hypothalamic sites, whereas NPY-induc ed anxiolysis appears to be mediated by Y1 receptors in the amygdala. Recen tly, NPY has been postulated to play a role in the regulation of ethanol co nsumption. The present study assessed the influence of intracerebroventricu lar (ICV) administration of NPY on the consumption of 10% ethanol or 2% suc rose in rats. Male Wistar rats were trained to self-administer 10% ethanol using the sucrose-substitution procedure and then implanted with an intrace rebroventricular (ICV) cannula. The effects of NPY (0-15 mu g) on ethanol c onsumption and sucrose consumption were then examined. ICV NPY infusion had no significant effects on the consumption of 10% ethanol, however, NPY sig nificantly increased the consumption of 2% sucrose, [F(1, 11) = 6.18, p = 0 .03]. These data suggest that ethanol intake and sucrose intake are differe ntially regulated by NPY. It is hypothesized that ICV infusion of NPY may b e affecting both Y1 and Y5 receptors producing increased consummatory drive and anxiolysis, two factors that have opposing effects on subsequent ethan ol consumption. Therefore, additional studies including site specific injec tion of NPY will be necessary to provide further insight into the role of N PY on ethanol consumption. (C) 2000 Elsevier Science Inc.