EFFECTS OF NEUROPEPTIDE-Y ON INGESTION OF FLAVORED SOLUTIONS IN NONDEPRIVED RATS

Recent evidence suggests that in addition to altering energy balance, neuropeptide Y (NPY) may stimulate ingestive behavior by modifying the orosensory quality of ingested substances. The present experiments in vestigated the effect of intracerebroventricular administration of NPY (5 mug/5 mul) on ingestion of various flavored solutions in nondepriv ed rats. Experiment 1 examined the effects of NPY on ingestion of a ra nge of concentrations of saline, sucrose, and saccharin solutions in s ingle-bottle tests. Results indicated that NPY stimulates ingestion of both sucrose and saccharin solutions that are normally palatable, In Experiment 2, palatable sucrose solutions flavored with either orange or black cherry Kool-Aid for separate training groups were selectively associated with NPY injection during single-bottle training sessions. Subsequent two-bottle preference tests showed a significant shift in preference toward the flavor paired with NPY during training. The resu lts of these experiments extend previous findings by showing that NPY can stimulate ingestion of sweet solutions regardless of caloric value and may potentiate sweet taste preference via an associative mechanis m.