Blockade of NK3R signaling during development. A, Effects of an NK3R antagonist, SB222200, on NKB-stimulated IP accumulation in COS-7 cells transiently transfected with an expression vector encoding the human NK3R. *, P < 0.05. B, Effects of sc injection of SB222200 (5 mg/kg) on Senktide-induced tail whips and wet dog shakes (n = 4). *, P < 0.05. C, Comparison of timing of VO in mice treated with daily sc injections of SB222200 (5 mg/kg) or VEH. The cumulative percentage of mice with VO as a function of age is shown (n = 25; VEH; open squares; and n = 21; SB222200; black triangles). D--F, qRT-PCR analysis of Kiss1, Tac2, and Tacr3 expression in the ARC of hpg females at age P24 (black bars) treated daily with SB222200 (5 mg/kg) or VEH beginning at age P12, compared with vehicle-treated WT littermates (white bars).