Table 2.

Association (k _on) and dissociation (k _off) rate constants of [³H]muscimol binding at room temperature in forebrain and cerebellar membranes of WT and δKO mice and in recombinant receptors expressed in HEK293 cells

	k on(M−1 × min−1)	k off(min−1)	K D(nM)
Forebrain membranes
WT mice	3.3 ± 0.2 × 108	0.53 ± 0.02	1.6
δKO mice	15 ± 3.1 × 108 **	1.67 ± 0.15***	1.1
WT‐δKO	1.4 ± 0.2 × 108	0.23 ± 0.02	1.6
Cerebellar membranes
WT mice	2.8 ± 0.2 × 108	0.47 ± 0.14	1.7
δKO mice	7.7 ± 0.2 × 108 **	1.11 ± 0.09*	1.4
WT‐δKO	1.2 ± 0.2 × 108	0.12 ± 0.03	1.0
Recombinant receptors
α1β2	n.d.	0.49 ± 0.07###
α1β2γ2	11 ± 0.6 × 108	1.78 ± 0.18	1.6
α1β2δ	n.d.	0.18 ± 0.03###
α6β2	n.d.	1.46 ± 0.05†††
α6β2γ2	6.3 ± 0.5 × 108, ### , †††	0.98 ± 0.02### , †††	1.6
α6β2δ	1.0 ± 0.1 × 108, ###	0.13 ± 0.03###	1.3
α6β3δ	1.8 ± 0.1 × 108, ###	0.13 ± 0.01###	0.72

Association (k _on) and dissociation rate constants (k _off) of [³H]muscimol binding in forebrain samples (association, n = 8, dissociation, n = 4 independent experiments made using individual animal forebrains) and in samples each of pooled from 3 mouse cerebella (n = 3 independent experiments made using pooled samples from 3 individual animal cerebella), and in recombinant receptors (n = 3–6 independent experiments each performed using receptors from independent transfections/expressions) (mean ± SEM). n.d., not determined. All experiments were performed in triplicate technical replicates. Statistical comparison of forebrain and cerebellar values: *p < 0.05, **p < 0.01, ***p < 0.001, significantly different from the corresponding WT value, unpaired t‐test. Statistical comparison of recombinant receptor values: ###p < 0.001, significantly different from the corresponding α1β2γ2 value; †††p < 0.001, significantly different from the corresponding α6β2δ value (one‐way anova followed by Tukey's post hoc test).