Study type: In vivo/preclinical · Status: Evidence verified by machine against declared source

Histochemical Characterization of the Dorsal Raphe-Periaqueductal Grey Dopamine Transporter Neurons Projecting to the Extended Amygdala.

eNeuro · 2022

Study scale: Mice were group housed (two to five animals per cage) in a colony under a 12/12 h light/dark cycle.

Product or molecular entity relationships

VIP: Exact entity relationship. Legacy citation custody associates this source with the catalog record; no product-relevance conclusion is implied.

Public plain-language summary

The published text is limited to the declared source and preserves reported uncertainty. It does not establish efficacy, safety, suitability, or evidence strength.

Research question

To characterize, the histochemical features of DADR-PAG neurons projecting to the CeA and BNST in mice, the current study combined retrograde labeling with Fluoro-Gold (FG) and histological techniques, focusing on TH, dopamine transporter (DAT), vasoactive intestinal peptide (VIP), and vesicular glutamate transporter 2 (VGlut2).

Study design

Not reported in the declared source.

Participants or experimental system

To identify putative DA neurons, DAT-Cre::Ai14 mice were used.

Study scale

Mice were group housed (two to five animals per cage) in a colony under a 12/12 h light/dark cycle.

Intervention or exposure

We applied immunohistochemistry and tracer methods focusing on DAT, TH, VIP, and VGlut2 in DAT-Cre mice (Bäckman et al., 2006), in which expression of Cre-recombinase is more restricted to DA neurons than in TH-Cre mice (Savitt et al., 2005; Lammel et al., 2015; Stuber et al., 2015).

Comparator

These results indicate that the two subpopulations might differently modulate the affective behaviors controlled by the extended amygdala.

Outcomes examined

We used the DA transporter (DAT) as a DA neuron marker and found that the DATDR-PAG neurons are composed of at least two subpopulations, DAT+/tyrosine hydroxylase (TH)+/vasoactive intestinal peptide (VIP)– putative DA neurons and DAT+/TH–/VIP+ putative non-DA glutamatergic neurons, innervating the extended amygdala similarly.

Key findings

It was observed that DATDR-PAG neurons consisted of the following two subpopulations: TH+/VIP– and TH–/VIP+ neurons.

Limitations and uncertainty

However, it remains unknown how heterogeneous subpopulations innervate the extended amygdala.

Product relevance and evidence boundary

This record is a published study, held here with its citation and review status. It is not a statement that any catalog item is effective, safe, or suitable for any use, and nothing in it is a dose or a protocol.

Evidence verified by machine against declared source. Verification is limited to the declared source and review scope. It does not mean independent replication or establish efficacy, safety, or suitability.