Enterostatin actions in the amygdala and PVN to suppress feeding in the rat

The pentapeptide enterostatin (ENT) inhibits feeding after injection into the cerebral ventricles. To localize the central sites of action of ENT, the peptide (0.01 to 3.3 nM) was microinjected into several brain regions and the intake of a high fat diet was measured. The results show that ENT injection in the paraventricular nucleus (PVN) or the amygdala (AMYG) produced a bi-phasic dose related feeding response, low doses of ENT inhibited feeding while higher dose had no effect. The effective dose to inhibit feeding in the AMYG was 10 fold lower than that in the PVN. No changes in food intake were observed after ENT injection into the ventromedial hypothalamus and nucleus tractus solitarius. The data provide further support that there are targets in the CNS for ENT and suggest that central ENT function is site specific.