TABLE I Permeability of the WT and... | Rockefeller University Press

TABLE I

Permeability of the WT and Mutant P2X₇ Receptors to Organic Cations

Receptors	I (pA/pF) KR	RP (mV) NMDG⁺			RP (mV) NMDG⁺-KR
WT	122 ± 8	−66.9 ± 0.2	−45.4 ± 2.5^{^b}	−36.5 ± 0.3	−24.6 ± 0.8^{^b}	−20.0 ± 0.5	−4.6 ± 1.0^{^b}
T15A	30 ± 3^{^a}	−68.9 ± 0.4	−53.8 ± 1.2^{^b}	−36.2 ± 0.8	−36.5 ± 0.5	−18.9 ± 0.7	−17.1 ± 1.1
T15E	94 ± 10	−54.9 ± 1.2^{^a}	−53.7 ± 1.5	−22.4 ± 0.7^{^a}	−21.8 ± 0.9	−14.8 ± 0.7^{^a}	−12.0 ± 0.5
T15K	187 ± 45	−35.5 ± 0.9^{^a}	−36.7 ± 0.6	−19.7 ± 0.6^{^a}	−17.1 ± 0.6	−14.9 ± 0.5^{^a}	−11.0 ± 0.6^{^b}
T15W	142 ± 11	−52.6 ± 0.9^{^a}	−47.4 ± 1.3	−23.0 ± 0.3^{^a}	−22.4 ± 0.5	−16.4 ± 0.8^{^a}	−14.4 ± 0.7
T15V	33 ± 4^{^a}	−65.3 ± 0.6	−48.5 ± 1.9^{^b}	−36.1 ± 0.3	−32.1 ± 0.6^{^b}	−20.6 ± 0.4	−17.5 ± 0.5^{^b}
T15S	47 ± 8^{^a}	−65.8 ± 0.3	−53.4 ± 0.8^{^b}	−36.6 ± 0.2	−31.7 ± 1.1^{^b}	−20.9 ± 0.4	−12.9 ± 1.7^{^b}
K17A	250 ± 25^{^a}	−65.5 ± 0.4	−45.2 ± 3.6^{^b}	−35.3 ± 0.2^{^a}	−23.9 ± 1^{^b}	−18.2 ± 0.6	−7.4 ± 0.4^{^b}
Δ18	180 ± 21	−50.3 ± 0.9^{^a}	−47.9 ± 1.2	−28.1 ± 0.6^{^a}	−28.1 ± 1.1	−17.2 ± 0.4	−15.6 ± 1.1

Receptors	I (pA/pF) KR	RP (mV) NMDG⁺			RP (mV) NMDG⁺-KR
WT	122 ± 8	−66.9 ± 0.2	−45.4 ± 2.5^{^b}	−36.5 ± 0.3	−24.6 ± 0.8^{^b}	−20.0 ± 0.5	−4.6 ± 1.0^{^b}
T15A	30 ± 3^{^a}	−68.9 ± 0.4	−53.8 ± 1.2^{^b}	−36.2 ± 0.8	−36.5 ± 0.5	−18.9 ± 0.7	−17.1 ± 1.1
T15E	94 ± 10	−54.9 ± 1.2^{^a}	−53.7 ± 1.5	−22.4 ± 0.7^{^a}	−21.8 ± 0.9	−14.8 ± 0.7^{^a}	−12.0 ± 0.5
T15K	187 ± 45	−35.5 ± 0.9^{^a}	−36.7 ± 0.6	−19.7 ± 0.6^{^a}	−17.1 ± 0.6	−14.9 ± 0.5^{^a}	−11.0 ± 0.6^{^b}
T15W	142 ± 11	−52.6 ± 0.9^{^a}	−47.4 ± 1.3	−23.0 ± 0.3^{^a}	−22.4 ± 0.5	−16.4 ± 0.8^{^a}	−14.4 ± 0.7
T15V	33 ± 4^{^a}	−65.3 ± 0.6	−48.5 ± 1.9^{^b}	−36.1 ± 0.3	−32.1 ± 0.6^{^b}	−20.6 ± 0.4	−17.5 ± 0.5^{^b}
T15S	47 ± 8^{^a}	−65.8 ± 0.3	−53.4 ± 0.8^{^b}	−36.6 ± 0.2	−31.7 ± 1.1^{^b}	−20.9 ± 0.4	−12.9 ± 1.7^{^b}
K17A	250 ± 25^{^a}	−65.5 ± 0.4	−45.2 ± 3.6^{^b}	−35.3 ± 0.2^{^a}	−23.9 ± 1^{^b}	−18.2 ± 0.6	−7.4 ± 0.4^{^b}
Δ18	180 ± 21	−50.3 ± 0.9^{^a}	−47.9 ± 1.2	−28.1 ± 0.6^{^a}	−28.1 ± 1.1	−17.2 ± 0.4	−15.6 ± 1.1

Peak amplitude of current (I) reached during a 4-s agonist application and reversal potential (RP) for WT and mutant receptors bathed in KR, NMDG⁺, NMDG⁺-KR, or NMEA⁺-KR solutions at the beginning (0.75 s; left columns) and end (right columns) of a 40-s application of 100 μM BzATP. Data shown are mean ± SEM values from at least six replicates per mutant.

Significant differences between WT and mutant receptors during a 40-s agonist application; P < 0.01.

Significant shifts in the reversal potential during a 40-s agonist application; P < 0.01.

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