FOS and Prader-Willi syndrome: In contrast, WAY-161503 administration failed to induce cFOS-IR at any level of the ARC in PWS-IC mice (Fig. 5b, d, f; bregma −1.46, t6 = 0.3, p = 0.75; bregma −1.70, t6 = 0.7, p = 0.487; Av, t6 = 0.8, p = 0.87).