Figure 2
Concentration–effect curves for SH-053-S-CH3 (a) and SH-053-R-CH3 (b) on α1β3γ2, α2β3γ2, α3β3γ2, and α5β3γ2 GABAA receptors, using an EC3 GABA concentration. Data points represent means±SEM from at least four oocytes from ⩾2 batches. A concentration of 1 μM SH-053-S-CH3 resulted in 126±7, 216±13, 207±24 and 297±11% of control current (at GABA EC3) in α1β3γ2, α2β3γ2, α3β3γ2, and α5β3γ2 receptors, respectively. A concentration of 1 μM SH-053-R-CH3 resulted in 124±7, 125±5, 120±5 and 186±19% of control current in α1β3γ2, α2β3γ2, α3β3γ2, and α5β3γ2, respectively. All these values were significantly different from those of the respective control currents (p<0.01, Student's t-test). For comparison, 1 μM of diazepam (which in contrast to 1 μM of SH-053-S-CH3 and SH-053-R-CH3 produces maximal stimulation of GABA EC3 current) resulted in 345±54, 508±58, 749±107 and 420±30% of control current for α1β3γ2, α2β3γ2, α3β3γ2, and α5β3γ2 receptors, respectively.
