AC-263093 (AC-093) functionally activates NPFFR2 and blocks activation of NPFFR1 with pKis of 6.9 and 7.0, respectively. AC-263093 has the potential for reversing opiate tolerance research. .
AC-263093 (10 mg/kg; i.p.) totally reverses the tolerance to Morphine Sulfate in rats[1].
[1]. David H Malin, et al. Reversal of morphine tolerance by a compound with NPFF receptor subtype-selective actions. Neurosci Lett. 2015 Jan 1:584:141-5.