Role of the rostral dorsomedial column of the periaqueductal gray during social defeat in rats.

Autor: de Almeida AP; Department of Anatomy, Institute of Biomedical Sciences, University of São Paulo, São Paulo, Brazil., Tamais AM; Department of Anatomy, Institute of Biomedical Sciences, University of São Paulo, São Paulo, Brazil., Zerbini C; Department of Anatomy, Institute of Biomedical Sciences, University of São Paulo, São Paulo, Brazil., Melleu FF; Department of Anatomy, Institute of Biomedical Sciences, University of São Paulo, São Paulo, Brazil., Canteras NS; Department of Anatomy, Institute of Biomedical Sciences, University of São Paulo, São Paulo, Brazil., Motta SC; Department of Anatomy, Institute of Biomedical Sciences, University of São Paulo, São Paulo, Brazil.
Jazyk: angličtina
Zdroj: Annals of the New York Academy of Sciences [Ann N Y Acad Sci] 2023 Dec; Vol. 1530 (1), pp. 138-151. Date of Electronic Publication: 2023 Oct 11.
DOI: 10.1111/nyas.15073
Abstrakt: Previous studies showed that the dorsal premammillary nucleus of the hypothalamus (PMD) is involved in social passive defensive behaviors likely to be meditated by descending projections to the periaqueductal gray (PAG). We focused on the rostral dorsomedial PAG (rPAGdm) to reveal its putative neural mechanisms involved in mediating social defensive responses. By combining retrograde tracing and FOS expression analysis, we showed that in addition to the PMD, the rPAGdm is influenced by several brain sites active during social defeat. Next, we found that cytotoxic lesions of the rPAGdm drastically reduced passive defense and did not affect active defensive responses. We then examined the rPAGdm's projection pattern and found that the PAGdm projections are mostly restricted to midbrain sites, including the precommissural nucleus, different columns of the PAG, and the cuneiform nucleus (CUN). Also, we found decreased FOS expression in the caudal PAGdm, CUN, and PMD after the rPAGdm was lesioned. The results support that the rPAGdm mediates passive social defensive responses through ascending paths to prosencephalic circuits likely mediated by the CUN. This study provides further support for the role of the PAG in the modulation of behavioral responses by working as a unique hub for influencing prosencephalic sites during the mediation of aversive responses.
(© 2023 The New York Academy of Sciences.)
Databáze: MEDLINE
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