Table 1.

Muscarinic receptor expression levels are not different in M₁-mEGFP and WT mice

		Bmax (fmol/mg)	Kd (nM)
Cortex	M1-WT	1,098 ± 353	0.50 ± 0.32
	M1-mEGFP	1,203 ± 291	0.56 ± 0.40
	M1-KO	582 ± 84	0.35 ± 0.24
Hippocampus	M1-WT	989 ± 244	0.54 ± 0.29
	M1- mEGFP	783 ± 177	0.88 ± 0.30
	M1-KO	426 ± 112	0.46 ± 0.18

Specific binding of [³H]NMS was used to quantify total muscarinic-receptor subtype levels in cortex and hippocampus from WT, homozygous M₁-mEGFP and M₁-knockout (M₁-KO) mice. Data are reported as mean ± SD from five animals. One-way ANOVA indicated no significant difference between WT and M₁-mEGFP in terms of both B_max (maximum specific binding) and the K_d. Values from M₁-KO mice allowed the contribution of the M₁-receptor subtype to be assessed (see text for details), with the assumption that elimination of the M₁ receptor does not substantially alter the expression of other muscarinic-receptor subtypes.