Neuropeptide FF receptor agonist (Ki values are 48.4 and 12.1 nM for NPFF1 and NPFF2, respectively). Potentiates the antinociceptive action of morphine in vivo and reverses the loss of morphine potency in tolerant animals. Also increases the amplitude of the sustained current of heterologously expressed acid sensing ion channel 3 (ASIC3) (EC50 ~ 50 μM).

CGP71683 is a competitive neuropeptide Y5 receptor antagonist (Ki: 1.3 nM) and shows no obvious activity at Y1 receptor (Ki >4000 nM) and Y2 receptor (Ki: 200 nM) in cell membranes.

BIBO 3304 is a potent, selective, nonpeptide neuropeptide Y Y1 receptor antagonist with IC50 of 0.38 and 0.72 nM for human and the rat Y1 receptor, respectively.