SB-616234-A counteracts SKF-99101H-induced hypothermia in guinea pigs in a dose-dependent manner, with an ED50 of 2.4 mg/kg orally. It also exhibits anxiolytic effects in rat and guinea pig models of maternal separation-induced vocalization, with ED50 values of 1.0 and 3.3 mg/kg intraperitoneally, respectively^[1].

Administered orally at doses ranging from 0.3 to 30 mg/kg, SB-616234-A inhibits ex vivo binding of [^3H]-GR125743 to 5-HT1B receptors in rat striatum in a dose-dependent manner, with an ED50 of 2.83 ± 0.39 mg/kg orally^[1].

SB-616234-A is distinguished by its high affinity for 5-HT1B receptors in CHO cells expressing the human variant (pKi 8.3 ± 0.2), displaying significant selectivity over other molecular targets except h5-HT1D receptors (pKi 6.6 ± 0.1). Its affinity for 5-HT1B receptors from rat and guinea pig striatum is high (pKi 9.2 ± 0.1). In binding studies using [35S]-GTPγS in a human recombinant cell line, SB-616234-A functions as a potent antagonist (pA2 value of 8.6 ± 0.2) without showing any agonistic activity. Similar antagonist activity is observed in rat striatal membranes (apparent pKB of 8.4 ± 0.5). At a concentration of 1 μM, SB-616234-A enhances electrically evoked [^3H]-5-HT release from cortical slices of guinea pig and rat brains, increasing the S2/S1 ratios to 1.8 and 1.6, respectively^[2].