SIMULTANEOUS ADMINISTRATION OF NEUROMEDIN B-10 AND GASTRIN-RELEASING PEPTIDE(1-27) REPRODUCES THE SATIATING AND MICROSTRUCTURAL EFFECTS OF BOMBESIN

Bombesin (BN) suppresses food intake more than an equimolar dose of ne uromedin B-10 (NMB-10) or gastrin-releasing peptide(1-27) [GRP(1-27)]. Because BN is active at both NMB- and GRP-preferring receptors, it is possible that its greater potency is due to the simultaneous activati on of both receptor subtypes. This hypothesis was tested by administer ing a mixture of NMB-10 and GRP(1-27). The results were consistent wit h our hypothesis: administration of the mixture of NMB-10 and GRP(1-27 ) produced an inhibition of intake volume and total licks equivalent t o that seen after an equimolar dose of BN and resulted in similar chan ges in the rate and pattern of licking.