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. 2021 May 17;26(11):6756–6772. doi: 10.1038/s41380-021-01145-7

Fig. 1. Experimental paradigm and behavioral readouts in SIR and GRP-housed female mice.

Fig. 1

Physiological and behavioral effects of SIR in female mice prior to conception. a Graphical representation of the experimental design. C57BL6/N female mice were housed in social isolation or in groups from PND21 onwards. After 5 weeks of social isolation or group housing, the animals were subjected to behavioral testing in the light-dark box test and social interaction test as well as to basal CORT measurements. After 7 weeks of social isolation or group housing, each group of SIR and GRP animals were split into two subgroups and treated with either vehicle (drinking water) or FLX (10 mg/kg). After 10 weeks, the animals were subjected to behavioral testing in the open field test and the social interaction test. A subgroup of animals was subjected to the forced swim test and to basal and stress-induced CORT measurements. These animals were excluded from mating. Weight gain was assessed weekly during the whole experimental timeline. The animals were then exposed to a timed mating procedure and their offspring were left undisturbed until adulthood. Maternal FLX treatment was continued throughout mating, pregnancy and the offspring’s pre-weaning period. Adult offspring were subjected to behavioral testing in the open field test, the social interaction test, the Y-maze test of spatial recognition memory, the temporal order test and the forced swim test (FST). Weight gain was monitored throughout development, while basal and stress-induced levels of CORT were measured before and after the FST, respectively. b Weight gain in SIR and GRP females during the first 7 weeks of isolation- or group-housing. **p < 0.01, reflecting the main effect of housing. c Basal plasma levels of CORT in SIR and GRP females at the 5-weeks testing timepoint; ***p < 0.001. d Latency to shuttle to the bright compartment of the light-dark box testing apparatus; ***p < 0.001. e Percent exploration time of an unfamiliar mouse compared to a dummy object and total distance moved during the social interaction test at the 5 weeks testing timepoint; *p < 0.05. f Weight gain in SIR-VEH, SIR-FLX, GRP-VEH and GRP-FLX animals in the three weeks following the start of FLX treatment (SIR-VEH vs GRP-VEH at PND86: °°p < 0.01; SIR-VEH vs GRP-VEH at PND94: °p < 0.05; SIR-FLX vs GRP-VEH at PND94: $p < 0.05; SIR-VEH vs GRP-VEH at PND100: °p < 0.05; SIR-FLX vs GRP-VEH at PND100: $$p < 0.01; GRP-FLX vs GRP-VEH at PND100: §§p < 0.01). g Total distance moved and time spent in the center zone in the open field test at the 10 weeks testing timepoint; ***p < 0.001, reflecting the main effect of SIR. h Percent exploration time of an unfamiliar mouse compared to a dummy object and total distance moved during the social interaction test at the 10 weeks testing timepoint; ***p < 0.001 between SIR-VEH and GRP-VEH; $p < 0.05 between SIR-VEH and SIR-FLX. i Time spent immobile in the FST test at the 10 weeks testing timepoint. $$p < 0.01 between SIR-VEH and SIR-FLX; ***p < 0.001 between SIR-VEH and GRP-VEH. j Basal and stress-induced levels of CORT. °°°p < 0.001, reflecting the main effect of testing condition; ***p < 0.001, reflecting the main effect of housing. N = 40 mice per group in b–e, N = 20 animals per group in f–h, and N = 10 animals per group in i–j. All values represent means ± s.e.m.