Parental Deprivation Induces N-Methyl-D-Aspartate-Receptor Upregulation in Limbic Brain Areas ofOctodon degus: Protective Role of the Maternal Call

[摘要] An optimal coordination between parentsand their offspring involves a sequence ofreciprocal behaviors to ensure the adequatecare of the young, which is critical for a healthyphysical, emotional, and social development.Parental deprivation, particularly an impairedchild-mother attachment, induces lastingchanges in emotional as well as in cognitivecapacities in later life. We assessed in the SouthAmerican precocial species,Octodon degus,whether alterations of glutamatergic functionof the limbic system induced by parentaldeprivation may be a neural correlate for suchbehavioral changes. Further, we analyzedwhether the mother's voice can protect fromseparation-induced changes of brain function.Changes of N-methyl-D-aspartate (NMDA)receptor expression were examined in thefollowing three groups of 2-week-oldOctodon deguspups: (I) control animals who remainedundisturbed with the family; (II) animals whowere repeatedly separated from the family andindividually placed in an unfamiliar environmentfor behavioral analysis (open field); and (III)animals who were treated like the group described under (lI) but were presented withmaternal vocalizations during separation.Relative to those in the control group I, theanimals in group II showed an upregulation ofNMDA receptor density in the (a)anteriorcingulate, prelimbic, infralimbic, and anteriorinsular cortices; (b)CA1/stratum radiatum;(c)CA1/stratum lacunosum moleculare andCA3/stratum radiatum; and (d)in the basomedialamygdaloid nucleus. Presentation of thematernal call during the separation period(group III) suppressed the separation-inducedNMDA receptor upregulation in all regions.The results demonstrate that early life eventscan influence the expression of transmitterreceptors and that maternal behavior, acting tocontrol the pup's socio-emotional environment,is a key factor for regulating such developmentalevents.

[学科分类] 精神健康和精神病学