CYN 154806 TFA, a cyclic octapeptide, is a potent and selective somatostatin sst2 receptor antagonist, with pIC 50 values of 8.58, 5.41, 6.07, 5.76 and 6.48 for human recombinant sst2, sst1, sst3, sst4 and sst5 receptors respectively In Vitro CYN 154806 TFA inhibits SRIF-induced increases in extracellular acidification (EAR) in CHO-K1 cells expressing human sst2 receptors (pKB 7.92). CYN 154806 TFA also blocks SRIF-induced increases [35S]-GTPγS binding in CHO-K1 cell membranes expressing human sst2 receptors as well as rat sst2(a) and rat sst2(b) receptors (pKB 7.81, 7.68 and 7.96, respectively). MCE has not independently confirmed the accuracy of these methods. They are for reference only. In Vivo CYN 154806 TFA (0.1 mg/kg; i.p.; 20 min before the administration of carbachol (CCh) (30 μg/kg) in M4 KO mice) dose-dependently and significantly reverses the decreases acid response to CCh in M4 but not M3 KO mice. MCE has not independently confirmed the accuracy of these methods. They are for reference only. Form:Solid IC50& Target:SSTR2