Skip to main content
. 2006 Aug 7;149(2):163–169. doi: 10.1038/sj.bjp.0706849

Table 1.

Voltage dependence and potency of extracellular 5-HT block of the NR1+NR2A wild-type and mutant receptors

Subunits δ K0.5 (0 mV) (mM) IC50 (μM) H n
WT 0.8±0.1 2.9±0.4 56±15 0.9±0.2 5
NR1(N0S) 0.2±0.01** 1.8±0.1* 1500±103** 0.9±0.0.1 5
NR2(N0Q) 0.5±0.1 1.2±0.1* 103±18 0.8±0.3 5
NR2(N+1Q) 0.8±0.1 12.9±0.9** 230±12** 1.0±0.1 5
The voltage dependence of block δ (i.e. the apparent fractional electrical depth experienced by the blocker) and the voltage-independent affinity of the blocker, K0.5 (0 mV) (Woodhull, 1973), was estimated according to the Boltzmann equation:
graphic file with name 0706849e1.jpg
where B is the fraction blocked, Bmax is the maximal fraction blocked, E0.5 is the voltage required for half-maximal block, E is the holding potential, z is the charge of the blocking molecule and R, T and F have their respective thermodynamic meanings.

IC50 values were determined at −120 mV. H is the Hill coefficient and n is the number of cells used. Statistically different from the corresponding values for wild-type subunits (t-test): *P<0.05, **P<0.01.