. 2023 Jan 18;24(3):1908. doi: 10.3390/ijms24031908

Table 2.

Receptor binding affinity of selected quinoxaline-2,3-diones at recombinant homomeric iGluRs, determined in radioligand binding assays (all values in μM).

cmpd	K_i [μM]
	Recombinant Homomeric iGluRs
	GluK1	GluK2	GluK3	GluK5	GluA2
CNQX (1)	1.3 ± 0.3 ^a	1.1 ± 0.1 ^b 1.5 ± 0.01 ^a	0.64 ± 0.05 ^a	8.4 ± 0.9 ^c,d	0.33 ± 0.03 ^a
DNQX (2)	0.65 ± 0.03 ^a	2.1 ± 0.3 ^a	0.36 ± 0.03 ^a	7.1 ± 0.9 ^a	0.25 ± 0.01 ^a
NBQX (3)	1.4 ± 0.4 ^e 12 ± 4 ^f 2.6 ± 0.1 ^d	2.3 ^e 13 ± 2 ^f 5.4 ± 1.2 ^d	3.2 ^e 24 ± 7 ^f 18 ± 8 ^b 3.4 ± 0.6 ^d	19 ± 8 ^e >100 ^f >100 ^c 152 ± 23 ^d	0.26 ± 0.04 ^f 0.077 ± 0.010 ^d
LU97175 (7)	0.088 ± 0.033 ^e 0.70 ± 0.12 ^d	0.31 ± 0.19 ^e 0.49 ± 0.06 ^d	0.022 ± 0.003 ^e 0.19 ± 0.029 ^d	6.9 ± 0.03 ^e 24 ± 4 ^d	1.52 ± 0.25 ^d
8 ^g	0.0038	4.1	0.68	20	nd
9 ^g	0.012	1.4	1.4	25	nd
10 ^g	0.43	23	nd	>30	nd
11 ^d	1.1 ± 0.1	2.0 ± 0.1	0.53 ± 0.15	43 ± 11	4.9 ± 0.6
12 ^d	0.80 ± 0.11	0.81 ± 0.08	0.28 ± 0.03	31 ± 4	6.2 ± 1.4
13 ^d	1.1 ± 0.1	0.91 ± 0.17	0.14 ± 0.02	26 ± 2	4.1 ± 0.6
14 ^d	0.80 ± 0.18	0.84 ± 0.19	0.33 ± 0.01	45 ± 4	6.0 ± 0.1
15 ^h	0.17 ± 0.01	0.52 ± 0.14	0.08 ± 0.01	5.2 ± 0.30	5.7 ± 0.3
16 ^d	>100	≈100	2.9 ± 0.3	>100	24 ± 6
17 ⁱ	≈100	>100	0.25 ± 0.01	>100	>100
18 ⁱ	0.15 ± 0.05	0.091 ± 0.01	0.13 ± 0.03	3.8 ± 0.1	0.23 ± 0.02
19 ^a	16 ± 1	9.5 ± 1.2	59 ± 3	nd	21 ± 2
20 ^j	1.2 ± 0.7	33 ± 3	37 ± 4	nd	>100

^a ref. [98], radioligands: GluA2, [³H]AMPA; GluK1-3, [³H](2S,4R)-4-methyl-Glu ([³H]SYM2081) or [³H]KA; ^b ref. [99], radioligand: [³H]KA; ^c ref. [13], radioligand: [³H]KA; ^d ref. [92], radioligands: GluA2, [³H]AMPA; GluK1, [³H]KA or (S)-2-amino-3-(6-[³H]-2,4-dioxo-3,4-dihydrothieno [3,2-d]pyrimidin-1(2H)-yl)propanoic acid ([³H]-(S)-NF608); GluK2,3,5, [³H]KA; ^e ref. [72], radioligand: [³H]KA; ^f ref. [100], radioligands: GluA2, [³H]AMPA; GluK1-3,5 and GluK5, [³H]KA; ^g ref. [94], radioligand: [³H]KA; ^h ref. [95], radioligands: GluA2, [³H]AMPA; GluK1, [³H]-(S)-NF608; GluK2,3,5, [isopropenyl-³H]-kainic acid; ⁱ ref. [97], radioligands: GluA2, [³H]AMPA; GluK1, [³H]-(S)-NF608; GluK2,3,5, [isopropenyl-³H]-kainic acid; ^j ref. [101], radioligands: GluA2, [³H]AMPA; GluK1, [³H]-(S)-NF608; GluK2,3, [³H]KA; nd—not determined.