GABA _B receptor

In the presence of 10 μM GABA, SSD114 hydrochloride at 25 μM significantly increases (to approximately 170% above basal levels) the [ ³⁵ S]GTPγS stimulation induced by GABA alone. SSD114 hydrochloride, added at 15 and 30 μM, induces a leftward shift of the GABA concentration-response curve with a slight concomitant increase of maximal GABA stimulation at the highest concentration. In the presence of both 15 and 30 μM SSD114 hydrochloride, the EC ₅₀ for GABA decreases by 2 and 2.5 fold, respectively, while the maximal stimulation (Emax) is potentiated only at the concentration of 30 μM, reaching 161±5.09% over the basal value .

The onset of loss of righting reflex (LORR) is reduced by pretreatment with SSD114 hydrochloride [F _(5,30) =4.55, P<0.005]. Post hoc analysis indicates that the onset of LORR is significantly lower in mouse groups pretreated with doses of SSD114 hydrochloride equal to or higher than 10 mg/kg than in vehicle-treated mice. The duration of LORR is increased by pretreatment with SSD114 hydrochloride [F _(5,30) =4.81, P<0.005]. Post hoc analysis indicates that the duration of LORR is significantly longer in mouse groups pretreated with 10 and 100 mg/kg SSD114 hydrochloride than in vehicle-treated mice.