Bilateral subdiaphragmatic vagotomy does not prevent the behavioral effects of systematically administered ceruletide...

To clarify the vagal mediation of behavioral changes following systematically administered CCK-like peptides, we examined the effects of subcutaneously injected ceruletide on several behavioral parameters. Ceruletide at a dose of 100 micrograms/kg reduced the rates of spontaneous locomotor activity and rearing, and also inhibited methylphenidate- and methamphetamine-induced hyperactivity in both sham-operated and vagotomized mice to same extent, whereas bilateral subdiaphragmatic vagotomy attenuated these behavioral parameters. These results indicate that the ascending sensory pathway mediating a peripheral CCK-elicited signal may not be responsible for producing the behavioral effects of systematically administered CCK-like peptides.