Table 2.

Total time of exploration of the juveniles and the objects during the training and the testing trial of the social recognition (SRT) and object recognition (ORT) tests, respectively, by PTH2-R-line mice when previously or not previously exposed to the experimental conditions. Data are presented as Mean ± SEM.

			Training	Testing
SRT	WT	Prior exposure	42.03 ± 5.75a	31.47 ± 4.35c
		No- Prior exposure	63.52 ± 3.02b	51.65 ± 4.63d
	PTH2-R-KO	Prior exposure	50.15 ± 4.15a	33.68 ± 5.05c
		No- Prior exposure	82.53 ± 5.28b	54.08 ± 7.52d
ORT	WT	Prior exposure	54.03 ± 7.26e	61.07 ± 6.30
		No- Prior exposure	68.12 ± 5.66	66.44 ± 5.71
	PTH2-R-KO	Prior exposure	79.65 ± 5.87f	67.36 ± 4.44
		No- Prior exposure	67.44 ± 5.62	62.14 ± 3.68

^a–boverall effect of the “prior exposure” condition during the training phase of the social recognition test p<0.001;

^c–doverall effect of the “prior exposure” condition during the testing phase of the social recognition test p=0.001;

^e–fPTH2-R-KO mice have a higher level of exploration compared with WT mice when previously exposed to the experimental conditions p=0.015.