Apomorphine suppresses ingestive behaviour in chronic decerebrate rats

To determine whether dopamine receptors in the brain stem can mediate inhibition of feeding behaviour male rats in which the forebrain was disconnected from the brain stem were studied. Such decerebrate rats do not approach food but display ingestive responses if infused intraorally with a 1 M solution of sucrose at 0.6 ml min-1. Intraperitoneal injection of 5 micrograms cholecystokinin octapeptide, a physiological satiety peptide, or 400 micrograms apomorphine, a dopamine D1-D2 receptor agonist, suppressed intake of the sucrose solution. The results support a role of brain stem dopamine receptors in the control of ingestive behaviour.