High-throughput synapse-resolving two-photon fluorescence microendoscopy for deep-brain volumetric imaging in vivo
Optical imaging has become a powerful tool for studying brains in vivo. The opacity of adult brains makes microendoscopy, with an optical probe such as a gradient index (GRIN) lens embedded into brain tissue to provide optical relay, the method of choice for imaging neurons and neural activity in deeply buried brain structures. Incorporating a Bessel focus scanning module into two-photon fluorescence microendoscopy, we extended the excitation focus axially and improved its lateral resolution. Scanning the Bessel focus in 2D, we imaged volumes of neurons at high-throughput while resolving fine structures such as synaptic terminals. We applied this approach to the volumetric anatomical imaging of dendritic spines and axonal boutons in the mouse hippocampus, and functional imaging of GABAergic neurons in the mouse lateral hypothalamus in vivo.
Almost all data needed to evaluate the conclusions in the paper are present in the paper or the supplementary materials; Raw image data for Figs. 2, 4 & 9 are available from Dryad, 10.5061/dryad.pr4t978
Article and author information
Howard Hughes Medical Institute
- Guanghan Meng
- Yajie Liang
- Wan-chen Jiang
- Rongwen Lu
- Joshua Tate Dudman
- Na Ji
National Institute of Neurological Disorders and Stroke
- Guanghan Meng
- Na Ji
National Institute on Drug Abuse
- Sarah Sarsfield
- Yeka Aponte
The funders had no role in study design, data collection and interpretation, or the decision to submit the work for publication.
Animal experimentation: All animal experiments were conducted according to the United States National Institutes of Health guidelines for animal research. Procedures and protocols were approved by the Institutional Animal Care and Use Committee at Janelia Research Campus, Howard Hughes Medical Institute (protocol number: 16-147)
- David Kleinfeld, University of California, San Diego, United States
- Received: August 5, 2018
- Accepted: December 20, 2018
- Accepted Manuscript published: January 3, 2019 (version 1)
- Accepted Manuscript updated: January 4, 2019 (version 2)
- Version of Record published: January 18, 2019 (version 3)
© 2019, Meng 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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