Table 2. Difference of Gene Expression Levels in the HPC and Caudate Putamen (Dorsal Striatum) of WT and Oprd1 ^−/− Mice.

				Hippocampus		Caudate putamen
Gene function	RefSeq	Gene title	Protein encoded	median±SEM	p value	median±SEM	p value
GABA signaling
	NM_172890	Slc6a11	GAT4	−1.01±0.19	0.884	1.42±0.15	0.031
	NM_133661	Slc6a12	GAT2	1.81±0.10	0.000	1.12±0.18	0.250
Glutamate signaling
	NM_177407	Camk2a	CamKIIa	−1.59±0.28	0.057	−1.83±0.27	0.000
	NM_013540	Gria2	GluR2	1.13±0.08	0.579	−1.47±0.13	0.005
	NM_001177656	Grin1	GluN1	−1.83±0.47	0.043	−1.34±0.06	0.004
	NM_008170	Grin2a	GluN2A	−1.35±0.12	0.016	−1.10±0.21	0.227
	NM_008171	Grin2b	GluN2B	−1.07±0.08	0.173	1.29±0.14	0.026
	NM_016976	Grm1	mGluR1	1.33±0.10	0.003	−1.01±0.04	0.977
	NM_001013385	Grm4	mGluR4	−1.05±0.13	0.535	1.27±0.03	0.000
	NM_182993	Slc17a7	VGlut1	−1.06±0.05	0.170	1.59±0.25	0.041
	NM_009200	Slc1a6	EAAT4	−1.35±0.10	0.015	−1.05±0.57	0.276
Monoamine signaling
	NM_009891	Chat	CHAT	1.61±0.17	0.009	1.00±0.24	0.506
	NM_173740	Maoa	MAOA	1.29±0.10	0.010	−1.17±0.08	0.008
	NM_010484	Slc6a4	SERT	1.13±0.40	0.487	−1.54±0.18	0.017
Neuronal markers
	NM_028755	Arpp21	ARPP21	−1.23±0.12	0.011	−1.30±0.06	0.003
	NM_021399	Bcl11b	CTIP2	−1.42±0.16	0.031	−1.53±0.13	0.002
	NM_007699	Chrm4	M4R	1.05±0.10	0.862	−1.24±0.05	0.001
	NM_199058	Gpr6	GPR6	−1.90±0.27	0.006	−1.52±0.11	0.002
	NM_010471	Hpca	HPCA	−1.26±0.15	0.033	−1.15±0.09	0.048
	NM_011866	Pde10a	PDE10A	−1.40±0.04	0.000	−1.10±0.09	0.216
	NM_018863	Pdyn	PDyn	−1.45±0.17	0.021	1.35±0.14	0.050
	NM_001002927	Penk	PEnk	−1.50±0.18	0.041	1.03±0.15	0.490
	NM_009311	Tac1	Subst P	−1.21±0.29	0.008	−1.37±0.07	0.002

A total of 67 genes encoding actors of GABA, glutamate or monoamine signaling, and neuronal markers (see Supplementary Table S2), were tested and only genes showing a significant fold-change difference are shown. Data are presented as fold-change Oprd1^−/− vs WT mice (median±SEM). Student's t-tests were performed on transformed data (Supplementary Information) to determine whether fold changes differed from 0 (no regulation; corresponds to±1 in table). Significant regulations are highlighted in bold.