Nomenclature	α1	α2	α3
HGNC, UniProt	GLRA1, P23415	GLRA2, P23416	GLRA3, O75311
Selective agonists (potency order)	glycine > β-alanine > taurine	glycine > β-alanine > taurine	glycine > β-alanine > taurine
Selective antagonists (IC50)	HU-308 (weak inhibition), PMBA, strychnine, pregnenolone sulphate (Ki 1.9x10-6 M), tropisetron (Ki 8.4x10-5 M), ginkgolide X (7.6x10-7 M), nifedipine (3.3x10-6 M), bilobalide (2x10-5 M), colchicine (3.24x10-4 M)	PMBA, strychnine, pregnenolone sulphate (Ki 5.5x10-6 M), tropisetron (Ki 1.3x10-5 M), HU-210 (9x10-8 M), WIN55212-2 (2.2x10-7 M), HU-308 (1.1x10-6 M), ginkgolide X (2.8x10-6 M), bilobalide (8x10-6 M), colchicine (6.4x10-5 M), 5,7-dichlorokynurenic acid (1.88x10-4 M)	strychnine, HU-210 (5x10-8 M), HU-308 (9.7x10-8 M), WIN55212-2 (9.7x10-8 M), (12E,20Z,18S)-8-hydroxyvariabilin (7x10-6 M), nifedipine (2.92x10-5 M)
Channel Blockers (IC50)	cyanotriphenylborate (1.3x10-6 M), ginkgolide B (6x10-7 – 8x10-6 M), picrotin (5.2x10-6 M), picrotoxinin (5.1x10-6 M), picrotoxin (6.3x10-6 M)	picrotoxinin (4.1x10-7 M), picrotoxin (2.3x10-6 M), ginkgolide B (3.7x10-6 – 1.14x10-5 M), picrotin (1.31x10-5 M), cyanotriphenylborate (>2x10-5 M)	picrotoxin (block is weaker when β subunit is co-expressed), picrotoxinin (4.3x10-7 M), ginkgolide B (1.8x10-6 M), picrotin (6x10-6 M)
Endogenous allosteric regulators	Extracellular H+ (Inhibition, endogenous), Zn2+ (Potentiation, endogenous; not affected by β subunit co-expression) (EC50 3.7x10-8 M), Cu2+ (Inhibition, endogenous; not affected by β subunit co-expression) (IC50 4x10-6 – 1.5x10-5 M), Zn2+ (Inhibition, endogenous) (IC50 1.5x10-5 M)	Zn2+ (Potentiation, endogenous; not affected by β subunit co-expression) (EC50 5.4x10-7 M), Cu2+ (Inhibition, endogenous) (IC50 1.7x10-5 M), Zn2+ (Inhibition, endogenous) (IC50 3.6x10-4 M)	Cu2+ (Inhibition, endogenous) (IC50 9x10-6 M), Zn2+ (Inhibition, endogenous) (IC50 1.5x10-4 M)
Selective allosteric regulators	anandamide (Potentiation) (EC50 3.8x10-8 M), HU-210 (Potentiation) (EC50 2.7x10-7 M), Δ9-tetrahydrocannabinol (Potentiation, ∼1500% potentiation) (EC50 ∼3x10-6 M)	Δ9-tetrahydrocannabinol (Potentiation, ∼230% potentiation) (EC50 ∼1x10-6 M)	Δ9-tetrahydrocannabinol (Potentiation, ∼1500% potentiation) (EC50 ∼5x10-6 M)
Radioligands (Kd)	[3H]strychnine	[3H]strychnine	[3H]strychnine
Functional characteristics	γ = 86 pS (main state); (+ β = 44 pS)	γ = 111 pS (main state); (+ β = 54 pS)	γ = 105 pS (main state); (+ β = 48)