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The nonapeptide system modulates numerous social behaviors through oxytocin and vasopressin activation of the oxytocin receptor (OXTR) and vasopressin receptor (AVPR1A) in the brain. OXTRs and AVPR1As are widely distributed throughout the brain and binding densities exhibit substantial variation within and across species. Although OXTR and AVPR1A binding distributions have been mapped for several rodents, this system has yet to be characterized in the spiny mouse (Acomys cahirinus). Here we conducted receptor autoradiography and in situ hybridization to map distributions of OXTR and AVPR1A binding and Oxtr and Avpr1a mRNA expression throughout the basal forebrain and midbrain of male and female spiny mice. We found that nonapeptide receptor mRNA is diffuse throughout the forebrain and midbrain and does not always align with OXTR and AVPR1A binding. Analyses of sex differences in brain regions involved in social behavior and reward revealed that males exhibit higher OXTR binding densities in the lateral septum, bed nucleus of the stria terminalis, and anterior hypothalamus. However, no association with gonadal sex was observed for AVPR1A binding. Hierarchical clustering analysis further revealed that co-expression patterns of OXTR and AVPR1A binding across brain regions involved in social behavior and reward differ between males and females. These findings provide mapping distributions and sex differences in nonapeptide receptors in spiny mice. Spiny mice are an excellent organism for studying grouping behaviors such as cooperation and prosociality, and the nonapeptide receptor mapping here can inform the study of nonapeptide-mediated behavior in a highly social, large group-living rodent.
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Vasopressin, and not oxytocin, receptor gene methylation is associated with individual differences in receptive joint attention in chimpanzees ( Pan troglodytes )
Abstract Joint attention (JA) is an important milestone in human infant development and is predictive of the onset of language later in life. Clinically, it has been reported that children at risk for or with a diagnosis of autism spectrum disorder (ASD) perform more poorly on measures of JA compared to neurotypical controls. JA is not unique to humans but has also been reported in great apes and to a lesser extent in more distantly related monkeys. Further, individual differences in JA among chimpanzees are associated with polymorphisms in the vasopressin and oxytocin genes,AVPR1AandOXTR. Here, we tested whether individual variation in DNA methylation ofOXTRandAVPR1Awere associated with performance on JA tasks in chimpanzees. We found that individual differences in JA performance was associated withAVPR1Amethylation, but notOXTRmethylation in the chimpanzees. The collective results provide further evidence of the role ofAVPR1Ain JA abilities in chimpanzees. The results further suggest that methylation values forAVPR1Amay be useful biomarkers for identifying individuals at risk for ASD or related neurodevelopmental disorders associated with impairments in JA abilities.
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- Award ID(s):
- 2021711
- PAR ID:
- 10419191
- Publisher / Repository:
- Wiley Blackwell (John Wiley & Sons)
- Date Published:
- Journal Name:
- Autism Research
- Volume:
- 16
- Issue:
- 4
- ISSN:
- 1939-3792
- Page Range / eLocation ID:
- p. 713-722
- Format(s):
- Medium: X
- Sponsoring Org:
- National Science Foundation
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