Table 3. Genotype and sex differences in saccharin (0.1, 0.2 and 0.4%) intake in a 4-day drinking-in-the-dark (DID) model in male (A) and female (B) nPE mice, and in saccharin preference after the 4-day DID model in male (C) and female (D) nPE mice.

In A and B, saccharin was presented 3 hours after the beginning of the dark cycle, and saccharin intake values were recorded after 4 hours of saccharin access for 4 days in the nPE+/+ and nPE−/− mice. In C and D, on the test day (day 5), both saccharin (0.1%, 0.2% or 0.4% concentration) and water were presented, and saccharin and water intake were recorded after 4 hours of saccharin access. Genotype difference: ^*p<0.05, ^**p<0.01 or ^***p<0.005 vs. nPE+/+ on the same day; Sex difference: &p<0.01 vs. the same genotype on the same day.

At 0.1% or 0.2% saccharin, 3-way ANOVA did not show any differences between the genotypes, sexes or any effects of their interaction. At 0.4% saccharin, 3-way ANOVA revealed significant effects of genotype [F (1, 64) = 53, p<0.000001], sex [F (1, 64) = 56, p<0.000001], and interaction between genotype and sex [F (1, 64) = 43, p<0.00005]. Post hoc analysis showed that: (1) between genotypes, both nPE−/− males and females had less intake from day 1 to day 4 than nPE+/+ ones [p<0.01 for all]; nPE−/− females had less intake at 8 and 24 hours than nPE+/+ ones [p<0.005 for both], and (2) between sexes, nPE+/+ males had less intake from day 1 to day 4 than nPE+/+ females [p<0.01 for all].

A. Saccharin intake in males (n=5)
Genotype	Day 1		Day 2		Day 3		Day 4
	nPE+/+	nPE−/−	nPE+/+	nPE−/−	nPE+/+	nPE−/−	nPE+/+	nPE−/−
0.1%, g/kg	0.16± 0.02	0.10± 0.03	0.19± 0.03	0.08± 0.02	0.25± 0.02	0.07± 0.04	0.28± 0.03	0.09± 0.03
0.2%, g/kg	0.29± 0.03	0.18± 0.03	0.31± 0.02	0.13± 0.02	0.48± 0.08	0.19± 0.03	0.53± 0.07	0.20± 0.04
0.4%, g/kg	0.65± 0.08 &&	0.32± 0.07*	0.69± 0.10 &&	0.38± 0.08*	0.78± 0.13 &&	0.32± 0.08*	0.81± 0.04 &&	0.33± 0.08**

B. Saccharin intake in females (n=5)
Genotype	Day 1		Day 2		Day 3		Day 4
	nPE+/+	nPE−/−	nPE+/+	nPE−/−	nPE+/+	nPE−/−	nPE+/+	nPE−/−
0.1%, g/kg	0.19± 0.03	0.04± 0.01	0.22± 0.04	0.12± 0.02	0.25± 0.01	0.11± 0.01	0.23± 0.02	0.07± 0.02
0.2%, g/kg	0.29± 0.08	0.24± 0.05	0.54± 0.05	0.22± 0.05	0.49± 0.04	0.23± 0.04	0.53± 0.02	0.12± 0.04
0.4%, g/kg	1.03± 0.05	0.38± 0.08***	1.03± 0.08	0.39± 0.02***	1.16± 0.04	0.36± 0.07***	1.07± 0.06	0.31± 0.08***

C. Saccharin preference in males (n=5). Genotype difference: *p<0.05 vs. nPE+/+ on the same day by Student’s t-tests.
Genotype	0.1%		0.2%		0.4%
	nPE+/+	nPE−/−	nPE+/+	nPE−/−	nPE+/+	nPE−/−
Preference	0.94±0.02	0.90±0.01	0.91±0.04	0.67±0.07*	0.95±0.01	0.92±0.02

D. Saccharin preference in females (n=5). Genotype difference: *p<0.05 vs. nPE+/+ on the same day by Student’s t-tests.
Genotype	0.1%		0.2%		0.4%
	nPE+/+	nPE−/−	nPE+/+	nPE−/−	nPE+/+	nPE−/−
Preference	0.92±0.02	0.90±0.01	0.93±0.02	0.71±0.01*	0.94±0.02	0.92±0.02