Genotypic differences in intruder-evoked immediate early gene activation in male, but not female, vasopressin 1b receptor knockout mice

Abstract

BackgroundThe neuropeptide arginine vasopressin (Avp) modulates social behaviors via its two centrally expressed receptors, the Avp 1a receptor and the Avp 1b receptor (Avpr1b). Recent work suggests that, at least in mice, Avp signaling through Avpr1b within the CA2 region of the hippocampus is critical for normal aggressive behaviors and social recognition memory. However, this brain area is just one part of a larger neural circuit that is likely to be impacted in Avpr1b knockout (−/−) mice. To identify other brain areas that are affected by altered Avpr1b signaling, genotypic differences in immediate early gene activation, i.e. c-FOS and early growth response factor 1 (EGR-1), were quantified using immunocytochemistry following a single exposure to an intruder.ResultsIn females, no genotypic differences in intruder-evoked c-FOS or EGR-1 immunoreactivity were observed in any of the brain areas measured. In males, while there were no intruder-evoked genotypic differences in c-FOS immunoreactivity, genotypic differences were observed in EGR-1 immunoreactivity within the ventral bed nucleus of the stria terminalis and the anterior hypothalamus; with Avpr1b −/− males having less EGR-1 immunoreactivity in these regions than controls.ConclusionsThese data are the first to identify specific brain areas that may be a part of a neural circuit that includes Avpr1b-expressing cells in the CA2 region of the hippocampus. It is thought that this circuit, when working properly, plays a role in how an animal evaluates its social context.Electronic supplementary materialThe online version of this article (doi:10.1186/s12868-016-0310-7) contains supplementary material, which is available to authorized users.

Sex dependent effects of post-natal penicillin on brain, behavior and immune regulation are prevented by concurrent probiotic treatment

“…For example, AVPR1a has a greater role in modulating anxiety in male mice 47,48 and blocking this receptor alters social play in males and females in an opposite fashion 49 . Similarly, sex related differences in AVPR1b dependent brain responses have been reported 50 . Altered AVPR expression is a consistent finding related to early-life penicillin exposure 18,41 and it is possible that sex differences in the vasopressinergic system may contribute to the sex dependent nature of the effects of this antibiotic on behaviour.…”

The association study of polymorphic variants of hypothalamic-pituitary-adrenal system genes (AVPR1B, OXTR) and aggressive behavior manifestation: a focus on social environment

“…The role of neuropeptides oxytocin and arginine vasopressin in regulation of social behavior, social cognition, individual stress response, depression and callous-unemotional traits has been reported to date [4,5]. In turn, impaired functioning of oxytocin and arginine-vasopressin 1b [5,6] and their receptors was demonstrated in animal models of exaggerated aggressive behavior, while a reduced oxytocin level was a predictor of aggression in humans [7]. The similarity in the amino acid sequence between oxytocin and arginine-vasopressin promotes differences in the affinity to their receptors [8], thus providing the resemblance in the processes that both neuropeptides modulate.…”

“…According to evolutionary research, specific sites in the AVPR1B gene were under positive selection related to domestication [29]a process involving the accumulation of prosocial traits. In addition, functional research indicated the relation of a reduced level of aggression in AVPR1b knockout mice [6]. Recent findings indicated the association between an impaired social behavior and altered expression of AVPR1B and OXTR genes in murine brain as a response to antibiotic treatment [30].…”

Social Context, Stress, Neuropsychiatric Disorders, and the Vasopressin 1b Receptor

“…Two different IEGs, cFos and early growth response factor 1 (EGR1), have been studied in both Avpr1b −/− male and Avpr1b −/− lactating females following a single exposure to an intruder male. While no genotypic differences in cFos immunoreactivity were observed in either Avpr1b −/− males or Avpr1b −/− lactating females, a genotypic difference in EGR1 immunoreactivity was observed within the ventral bed nucleus of the stria terminalis (BNSTV) and the anterior hypothalamus (AHA), with male Avpr1b −/− mice having reduced EGR1 immunoreactivity in both brain regions relative to controls (Wersinger et al, 2002 ; Witchey et al, 2016 ). As both the BNSTV and AHA are implicated in the neural circuitry of aggression, we hypothesize that they may be part of the downstream circuit influenced by Avpr1b expression in the CA2 region of the hippocampus.…”

“…Further, increases in cFos expression are observed within the LS following intermale, interfemale, and maternal aggression (Kollack-Walker and Newman, 1995 ; Delville et al, 2000 ; Davis and Marler, 2003 ; Hasen and Gammie, 2005 ). It is also important to mention that the LS lies upstream of the BNSTV and AHA (Ferris et al, 1990 ; Staiger and Wouterlood, 1990 ); thus providing a potential circuit that might explain the EGR-1 data in Avpr1b −/− males (Witchey et al, 2016 ).…”