Residues at the tip of the pore loop of NR3B-containing NMDA receptors determine Ca2+ permeability and Mg2+block

BMC Neuroscience

Table 2 Ca²⁺ permeability of coexpressed mutant NMDAR subunits: Reversal potentials and P_Ca²⁺/P_mono ratios

	E_rev(Gly)[mV] (n)	P_Ca²⁺/P_mono± SEM (Gly) (n)	E_rev(Glu/Gly)[mV] (n)	P_Ca²⁺/P_mono± SEM (Glu/Gly) (n)
NR1-3a/NR2B	-23.1 ± 3.93 (5)	3.1 ± 0.65 (5)	-29.3 ± 1.79 (5)	2.3 ± 0.21 (5)
NR1-3a/NR2B(GN)	-15.3 ± 5.06 (5)	4.5 ± 1.02 (5)	-32.3 ± 2.73 (5)	2.0 ± 0.27 (5)
NR1-3a(GS)/NR2B	-39.7 ± 2.05 (5)	1.4 ± 0.13 (5)	-44.7 ± 2.20 (5)	1.1 ± 0.10 (5)
NR1-3a(GS)/NR2B(GN)	-46.8 ± 5.14 (5)	1.0 ± 0.18 (5)	-44.1 ± 1.24 (5)	1.1 ± 0.07 (5)
NR1-3a/NR3B	-68.4 ± 5.65 (9)	0.4 ± 0.11 (9)	-64.9 ± 4.26 (8)	0.5 ± 0.11 (8)
NR1-3a/NR3B(NR)	-34.7 ± 5.27 (9)	1.7 ± 0.61 (9)	-28.2 ± 1.71 (8)	2.5 ± 0.21 (8)
NR1-3a/NR3B(GN)	-49.2 ± 7.66 (9)	0.4 ± 0.31 (9)	-36.3 ± 2.75 (8)	1.7 ± 0.21 (8)
NR1-3a/NR3B(NS)	-46.8 ± 10.03 (5)	1.0 ± 0.57 (5)	-20.4 ± 4.74 (4)	2.5 ± 0.79 (4)
NR1-3a(GS)/NR3B	-64.5 ± 12.62 (5)	0.2 ± 0.20 (5)	-76.2 ± 7.92 (5)	0.1 ± 0.07 (5)
NR1-3a(GS)/NR3B(NR)	-83.1 ± 14.72 (5)	0.1 ± 0.13 (5)	-93.2 ± 10.33 (5)	0.1 ± 0.04 (5)
NR1-3a(GS)/NR3B(GN)	-54.6 ± 7.02 (5)	0.3 ± 0.11 (5)	-59.5 ± 7.61 (5)	0.3 ± 0.07 (5)
NR1-3a(GS)/NR3B(NS)	-38.0 ± 1.16 (5)	0.7 ± 0.03 (5)	-38.2 ± 2.74 (5)	0.7 ± 0.10 (5)

Overview of reversal potentials (E_revs) and calculated P_Ca²⁺/P_mono ratios of diheteromers featuring N and N+1 site mutant NMDAR subunits measured upon activation by either glycine alone (Gly, 10 μM) or Gly in addition to glutamate (Glu, 100 μM). Reversal potentials were measured in 8 mM Ca²⁺ Ringer. Errors represent the standard error of the mean (SEM). n = number of cells.

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