Arginine vasopressin (AVP) is a neuropeptide which acts centrally to modulate numerous social behaviors. One receptor subtype through which these effects occur is the AVP 1a receptor (AVPR1A). The modulatory effects of Avp via the AVPR1A varies by species as well as sex, since both AVP and the AVPR1A tend to be expressed more prominently in males. Beyond these neuromodulatory effects there are also indications that the AVP system may play a role in early development to, in part, organize sex‐specific neural circuitry that is important to sexually dimorphic social behaviors in adulthood. However, to date, AVP's role in early development is poorly understood, particularly with respect to its differential effect on males and females. In order to determine the timing and distribution of the AVP system in early brain development, we examined the brains of male and female C57BL/6J mice between embryonic day (E) 12.5 and postnatal day (P) 2 and quantified
The transient receptor potential cation channel 2 (TRPC2) conveys pheromonal information from the vomeronasal organ (VNO) to the brain. Both male and female mice lacking this gene show altered sex‐typical behavior as adults. We asked whether TRPC2, highly expressed in the VNO, normally participates in the development of VNO‐recipient brain regions controlling mounting and aggression, two behaviors affected by TRPC2 loss. We now report significant effects of TRPC2 loss in both the posterodorsal aspect of the medial amygdala (MePD) and ventromedial nucleus of the hypothalamus (VMH) of male and female mice. In the MePD, a sex difference in neuron number was eliminated by the TRPC2 knockout (KO), but the effect was complex, with fewer neurons in the
- NSF-PAR ID:
- 10439930
- Publisher / Repository:
- Wiley Blackwell (John Wiley & Sons)
- Date Published:
- Journal Name:
- Journal of Comparative Neurology
- Volume:
- 531
- Issue:
- 15
- ISSN:
- 0021-9967
- Page Range / eLocation ID:
- p. 1550-1561
- Format(s):
- Medium: X
- Sponsoring Org:
- National Science Foundation
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Abstract Avp andAvpr1a mRNA using qPCR and AVPR1A protein using receptor autoradiography. The mRNA forAvp was measurable in males and females starting at E14.5, with males producing more than females, whileAvpr1a mRNA was found as early as E12.5, with no difference in expression between sexes. AVPR1A binding was observed in both sexes starting at E16.5, and while there were no observed sex differences, binding density and the number of neuroanatomical areas did increase over time. These data are significant as they provide the first whole‐brain characterization of the vasopressin system in the embryonic mouse. Further, these findings are consistent with data from other species, that have documented a sex difference in the vasopressin system during early brain formation. -
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Abstract Background Sexually dimorphic mating behaviors differ between sexes and involve gonadal hormones and possibly sexually dimorphic gene expression in the brain. However, the associations among the brain, gonad, and sexual behavior in teleosts are still unclear. Here, we utilized germ cells-free
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Abstract Background The etiology of sporadic Parkinson’s disease (PD) remains uncertain, but genetic, epidemiological, and physiological overlap between PD and inflammatory bowel disease suggests that gut inflammation could promote dysfunction of dopamine-producing neurons in the brain. Mechanisms behind this pathological gut-brain effect and their interactions with sex and with environmental factors are not well understood but may represent targets for therapeutic intervention.
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