Paternal Deprivation and Female Biparental Family Rearing Induce Dendritic and Synaptic Changes in Octodon degus: II. Nucleus Accumbens.

Abstract

While the majority of studies on the importance of parental caregiving on offspring behavioral and brain development focus on the role of the mother, the paternal contribution is still an understudied topic. We investigated if growing up without paternal care affects dendritic and synaptic development in the nucleus accumbens of male and female offspring and if replacement of the father by a female caregiver "compensates" the impact of paternal deprivation. We compared (a) biparental rearing by father and mother, (b) monoparental care by a single mother, and (c) biparental rearing by two female caregivers. Quantitative analysis of medium-sized neurons in the nucleus accumbens revealed that growing up without father resulted in reduced spine number in both male and female offspring in the core region, whereas spine frequency was only reduced in females. In the shell region, reduced spine frequency was only found in males growing up in a monoparental environment. Replacement of the father by a female caregiver did not "protect" against the effects of paternal deprivation, indicating a critical impact of paternal care behavior on the development and maturation of neuronal networks in the nucleus accumbens.