Rearing conditions and domestication background determine regulation of hippocampal cell proliferation and survival in adulthood - Laboratory CD1 and C57Bl/6 mice versus wild house mice

Brain development is sensitive to an individual's interaction with its environment. Deprivation of natural environmental stimulation especially in the phase after weaning has long-lasting consequences on neuroplasticity. However, previous findings concerning the effects of rearing environment on adult hippocampal cell proliferation and neurogenesis in rodents remain contradictory.To address the question, whether the variability of hippocampal plasticity in response to environmental conditions is a unique feature at least in mice, the present study examined the effects of social and physical deprivation during brain development on hippocampal cell production and survival in adults of three mouse strains (Mus musculus) with different domestication background: outbred CD1, inbred C57Bl/6 and the F2-descendants of wild-caught house mice.Wheel running increased cell proliferation rates in the dentate gyrus of CD 1 and C57Bl/6 mice reared under socially and physically deprived conditions, but not from enriched conditions. In wild house mice, neither the rearing conditions nor the wheel-running challenge did affect proliferative activity.This indicates, on the one hand, that wild house mice are more robust in their regulation of hippocampal cell proliferation against environmental influences and, on the other hand, that domestication and rearing background of laboratory animals impact neuroplastic potentials and responsiveness to external stimuli in adulthood.

► Wheel-running effect on hippocampal cell production depends on rearing history. ► Rearing conditions or running alters cell production only in C57Bl/6 and CD1 mice. ► No effect of rearing conditions or running on cell proliferaton in wild house mice. ► No differences in running performance between strains. ► Only in wild house mice, running activity depends on rearing conditions.