No evidence from complementary data sources of a direct glutamatergic projection from the mouse anterior cingulate area to the hippocampal formation
Abstract
The connectivity and interplay between the prefrontal cortex and hippocampus underpin various key cognitive processes, with changes in these interactions being implicated in both neurodevelopmental as well as neurodegenerative conditions. Understanding the precise cellular connections through which this circuit is organised is, therefore, vital for understanding these same processes. Overturning earlier findings, a recent study described a novel excitatory projection from anterior cingulate area to dorsal hippocampus. We sought to validate this unexpected finding using multiple, complementary methods: anterograde and retrograde anatomical tracing, using anterograde and retrograde AAVs, monosynaptic rabies tracing and the Fast Blue classical tracer. Additionally, an extensive data search of the Allen Projection Brain Atlas database was conducted to find the stated projection within any of the deposited anatomical studies, as an independent verification of our own results. However, we failed to find any evidence of a direct, monosynaptic glutamatergic projection from mouse anterior cingulate cortex to the hippocampus proper.
Data availability
All data generated or analysed during this study are included in the manuscript and supporting file; Source Data file have been provided for Figure 3.
Article and author information
Author details
Funding
Biotechnology and Biological Sciences Research Council (BB/P001475/1)
- Michael T Craig
Medical Research Council (MR/N0137941/1)
- Gabriella Margetts-Smith
- Erica S Brady
Wellcome Trust (108891/B/15/Z)
- Steliana Yanakieva
The funders had no role in study design, data collection and interpretation, or the decision to submit the work for publication.
Reviewing Editor
- Mathieu Wolff, CNRS, University of Bordeaux, France
Ethics
Animal experimentation: All UK-based research was carried out in accordance with the UK Animals (Scientific Procedures) Act 1986, and was subject to local ethical review by the Animal Welfare and Ethical Review Board at the University of Exeter or University of Glasgow. All surgical procedures were carried out using aseptic technique under isoflurane anaesthesia, with additional analgesia provided peri- and post-operatively. Every effort was made to minimise animal suffering.
Version history
- Preprint posted: January 26, 2022 (view preprint)
- Received: January 26, 2022
- Accepted: August 3, 2023
- Accepted Manuscript published: August 7, 2023 (version 1)
- Version of Record published: August 14, 2023 (version 2)
Copyright
© 2023, Andrianova et al.
This article is distributed under the terms of the Creative Commons Attribution License permitting unrestricted use and redistribution provided that the original author and source are credited.
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