. 2016 Mar 11;12(2):313–329. doi: 10.1007/s11302-016-9506-7

Table 1.

Expression levels (B _max) and K _D values of the wt human A_2A receptor and the A_2A cysteine mutants. Data are obtained by homologous binding versus [³H]CGS21680 (5 nM; upper table) and [³H]NECA (3 nM; lower table). Data are means ± SEM of the three independent experiments, unless otherwise noted. ELISA data are shown for comparison between the wt hA_2AAR and the mutants

[³H]CGS21680	K _D ± SEM (nM)	B _max ± SEM (fmol/mg of protein)	ELISA (%)
hA_2A wt	127 ± 3	478 ± 70	100 ± 16
hA_2A C166S	110 ± 4^{b, ns}	230 ± 38^{a, **}	40.1 ± 12.4^***
hA_2A C159S	46.2 ± 6.5^{a, ***}	421 ± 51^ns	227 ± 4^***
hA_2A C146S – C159S	124 ± 10^{b, ns}	352 ± 78^{b, ns}	87.4 ± 15.2^*
[³H]NECA
hA_2A wt	6.33 ± 1.42	129 ± 13	100 ± 16
hA_2A C146S	25.8 ± 5.9^*	152 ± 17 ^ns	23.0 ± 6.5^***

^n.d not determined, because of the low expression of the hA_2A C146S mutant; ^ns not significantly different from wt hA_2AAR (determined using the two-tailed t test)

^a n = 4

^b n = 5

^* p < 0.05

^** p < 0.01

^*** p < 0.001