311309-27-0

RFRP-3 efficiently inhibits forskolin-induced production of cAMP with an IC ₅₀ of 0.7 nM. Scatchard-plot analysis shows that ¹²⁵ I-labelled hRFRP-3 has a single class of high-affinity binding sites for the membrane fractions of CHO cells expressing rat OT7T022, the K _d value and the B _max values are 0.19 nM and 1.3 pM, respectively.RFRP-3 specifically stimulate cells transfected with a new orphan 7TMR, OT7T022, it binds to OT7T022 as a specific ligand with high affinity (K _d = 0.19 nM).RFRP-3 (10 ^-8 to 10 ^-14 M) has no effect on LH and FSH levels alone, but when it combines with GnRH, LH and FSH secretion is significantly reduced by the combination.