Neuropeptide Y has a stimulatory action on feeding behavior in goldfish (Carassius auratus)

The purpose of the present study was to elucidate the possible role of neur opeptide Y (NPY) in the feeding regulation in fish. We examined the effects of intracerebroventricular (i.c.v.) or intraperitoneal (i.p.) neuropeptide Y administration on food intake in satiated goldfish, at different time in tervals postinjection (0-2, 2-8 and 0-8 h). Food intake was significantly i ncreased by i.c.v. administered neuropeptide Y (1 mu g) at 2 h postinjectio n, while no significant differences in food intake were observed after i.p. treatment. The neuropeptide Y receptor antagonist, neuropeptide Y-(27-36), totally counteracted the stimulatory action of neuropeptide Y on feeding. The possible involvement of neuropeptide Y in the eating behavior evoked by food deprivation has been investigated. Food deprivation by either 24 or 7 2 h significantly increased feeding, and the neuropeptide Y receptor antago nist attenuated such feeding stimulation. From our findings, we suggest, fi rst, that neuropeptide Y is involved in feeding central regulation in goldf ish, acting via specific neuropeptide Y receptors, and second, that hypotha lamic neuropeptide Y would be released in response to food deprivation, con tributing to generate the consequent eating behavior stimulation in Carassi us auratus. (C) 1999 Elsevier Science B.V. All rights reserved.