摘要

The aim of this study was to ascertain the roles of neuropeptide W (NPW) and obestatin in feeding and endocrine regulations and their interactions with leptin, corticosterone, and insulin, three key hormones involved in metabolic homeostasis. Plasma variations were measured in obese hyperphagic Zucker rats either following a one-day fast, or after chronic food restriction (one-third less food than normal for three weeks) Obestatin did not vary by feeding condition, and did not differ between lean and obese rats, it likely does not play any role in feeding regulation. NPW did not vary with one-day fasting, but was higher in obese rats than in lean rats under satiated (+38%) and fasting (+44%; P < 0 01) conditions In chronically food-restricted obese rats that lost about 10% of their initial body weight, NPW decreased by 18% (P < 0 02), in parallel with a similar decrease in plasma insulin (P < 0 03), and a 10% decrease of plasma leptin (P < 0.001). Corticosterone levels in obese rats were much higher than in lean rats, and increased (P < 0.0001) after chronic food restriction, but not after a short fast. Prolonged food restriction was therefore stressful for obese rats. Long-term food shortage associated with insulin, leptin and corticosterone changes is then a critical factor for the regulation of NPW The NPW up-regulation in hyperphagic conditions and its down-regulation in hypophagic conditions, is compatible with an anorexigenic role of this peptide.

  • 出版日期2010-10