Effect of a selective neuropeptide Y Y(2) receptor antagonist, BIIE0246 on neuropeptide Y release.

We have examined the selective neuropeptide Y Y(2) receptor antagonist, (S)-N(2)-[[1-[2-[4-[(R,S)-5,11-dihydro-6(6h)-oxodibenz[b, e]azepin-11-yl]-1-piperazinyl]-2-oxoethyl]cyclopentyl]acetyl ]-N-[2-[1 ,2-dihydro-3,5(4H)-dioxo-1,2-diphenyl-3-H-1,2, 4-triazol-4-yl]ethyl]-argininamid (BIIE0246) on neuropeptide release from rat hypothalamic slices in vitro. BIIE0246 prevented neuropeptide Y-(13-36)-induced reduction in basal and K(+)-stimulated neuropeptide Y release. Addition of BIIE0246 alone enhanced K(+)-stimulated neuropeptide release, without affecting basal release. These data are consistent with anatomical and functional studies suggesting a pre-synaptic role for neuropeptide Y Y(2) receptors in regulating rat hypothalamic neuropeptide Y release in the rat.