Table 1.

Two-electrode voltage clamp recordings of GHB-elicited currents from X. laevis oocytes expressing different α(1,4,6)- and α4F71L-containing GABA_A receptors

	I/IGABA, max ± SEM	EC50 (95% CI; M)	nH (95% CI)	n
α4β1δ	0.74 ± 0.1	1.4 × 10−7 (0.3–6.6 × 10−7)	0.52 (0.09–0.95)	5
α4β1γ2L	0.02 ± 0.02*	†	†	4
α4β1	0.03 ± 0.002*	†	†	4
α4β2δ	0.53 ± 0.06	8.4 × 10−3 (4.0–17 × 10−3)	1.6 (0.52–1.8)	4
α4β2γ2L	†	†	†	5
α4β2	‡	‡	‡	22
α4β3δ	0.76 ± 0.08	1.0 × 10−3 (0.6–2.8 × 10−3)	1.3 (0.6–1.2)	6
α4β3γ2L	†	†	†	5
α4β3	†	†	†	5
α1β1δ	0.02 ± 0.01§	¶	¶	8
α6β1δ	0.06 ± 0.02§	¶	¶	10
Mutant data
α4F71Lβ1 GHB	†	†	†	6
α4F71Lβ1δ GHB	†	†	†	10
α4F71Lβ1 GABA	§	7.2 × 10−7 (5.5–9.3 × 10−7)	0.89 (0.7–1.1)	4
α4F71Lβ1δ GABA	§	1.8 × 10−7 (1.3–2.6 × 10−7)	1.03 (0.7–1.4)	6

*Normalized current at 3 mM GHB.

^†Because of high estimated EC₅₀ value, no curve could be generated.

^‡GABA-induced currents were not high enough to estimate GHB responses.

§GABA concentrations used to determine maximum current for each subunit were, respectively, 10 μM, 1 mM, 10 μM, 1 μM, 1 mM, 10 μM, 10 μM, 1 mM, 10 μM, 10 mM, and 1 mM.

^¶I/I_GABA not applicable.