Rôle des récepteurs mu-opioïdes dans la régulation d'un axe intestin-cerveau de contrôle de la prise alimentaire

Using portal infusions of agonists and/or antagonists of mu-opioid receptors (MORs) in conscious rodents, we have shown that the MORs present in the walls of the portal vein control a gut-brain nervous circuit of induction of intestinal gluconeogenesis, a function controlling hunger. In a second step, we have shown that peptides and protein digests promote a MOR-dependent induction of intestinal gluconeogenesis. The peptides have no effect in mice knockout for MOR, which are also insensitive to the satiety induced by protein diets. In addition, portal infusions of MOR-modulators have no effect on food intake in mice deficient for intestinal gluconeogenesis. Thus, the regulation by the portal MORs and peptides of a gut-brain neural circuit of induction of intestinal gluconeogenesis is a causal link in the phenomenon of satiety induced by dietary protein.