Long‐term consequences of peri‐adolescent social isolation on social preference, anxiety‐like behaviour, and vasopressin neural circuitry of male and female rats. (16th November 2021)

• Record Type: Journal Article
• Authors: Kinley, Brianna L.; Kyne, Robert F.; Lawton‐Stone, Tamijah S.; Walker, Deena M.; Paul, Matthew J.
• Is Part Of: European journal of neuroscience. Volume 54:Number 11(2021)
• Page Start: 7790
• Page End: 7804
• Publication Date: 2021-11-16
• Subjects: anxiety‐like behaviour -- isolation -- postweaning social -- sex differences -- social preference -- vasopressin; Nervous system -- Periodicals; 612.8
• DOI: 10.1111/ejn.15520
• Languages: English
• ISSNs: 0953-816X

Abstract

Abstract: Social isolation during the juvenile and adolescent stages (peri‐adolescent social isolation) can have long‐term consequences for behavioural and neural development. Most of this research, however, has relied on data from males, and very few studies have included both sexes. The present study investigated the impact of peri‐adolescent social isolation on social preference, anxiety‐like behaviour, and vasopressin neural circuitry of male and female Long Evans rats. Rats were either housed alone for 3 weeks beginning at weaning (Isolated) or in groups (Group‐housed). In adulthood, rats were tested in social preference, open field, marble burying, and light/dark box tests, and brains were processed for vasopressin immunohistochemistry. Isolated males exhibited a lower social preference score and spent more time in the light zone of the light/dark box than their group‐housed counterparts. Isolated and Group‐housed females did not differ in these measures. Peri‐adolescent social isolation did not alter vasopressin fibre density in target areas known to influence social and anxiety‐like behaviours (the lateral septum or lateral habenula), but increased fibre density in an output pathway of the circadian pacemaker (projections to the paraventricular nucleus of the thalamus); an effect detected across both sexes. A previously unreported sex difference was also detected for vasopressin fibre density in the paraventricular nucleus of the thalamus (females > males). These findings demonstrate long‐term consequences of peri‐adolescent social isolation on social preference, anxiety‐like behaviour, and the circadian vasopressin pathway and suggest that socio‐affective development of males is more vulnerable to social stressors during the juvenile and adolescent stages. Abstract : Social isolation during the juvenile and adolescent stages (peri‐adolescent social isolation) can have long‐term consequences for behavioural and neural development. Most of this research, however, has relied on data from males. In the present study, we find that peri‐adolescent social isolation has a more robust effect on social preference, and potentially anxiety‐like behaviour, of male rats than female rats. Effects (or lack thereof) on vasopressin fibre density did not differ between the sexes. These findings suggest that social development of males is more vulnerable to social stressors during the juvenile and adolescent stages.