Magnetic resonance measurements of cellular and sub-cellular membrane structures in live and fixed neural tissue
- Eunice Kennedy Shriver National Institute of Child Health and Human Development, National Institutes of Health, United States
- National Institute of Neurological Disorders and Stroke, National Institutes of Health, United States
- National Institute of Mental Health, National Institutes of Health, United States
- National Heart, Lung, and Blood Institute, National Institutes of Health, United States
- Zhejiang University, China
Abstract
We develop magnetic resonance (MR) methods for real-time measurement of tissue microstructure and membrane permeability of live and fixed excised neonatal mouse spinal cords. Diffusion and exchange MR measurements are performed using the strong static gradient produced by a single-sided permanent magnet. Using tissue delipidation methods, we show that water diffusion is restricted solely by lipid membranes. Most of the diffusion signal can be assigned to water in tissue which is far from membranes. The remaining 25% can be assigned to water restricted on length scales of roughly a micron or less, near or within membrane structures at the cellular, organelle, and vesicle levels. Diffusion exchange spectroscopy measures water exchanging between membrane structures and free environments at 100 s-1.
Data availability
Source data for all Figures 1-9 in the manuscript have been provided as supporting files.
Article and author information
Author details
Nathan H Williamson
Melanie Falgairolle
Michael James O'Donovan
Funding
Eunice Kennedy Shriver National Institute of Child Health and Human Development (Intramural Research Program (IRP))
- Nathan H Williamson
- Rea Ravin
- Dan Benjamini
- Teddy X Cai
- Ruiliang Bai
- Peter J Basser
National Institute of Neurological Disorders and Stroke (IRP)
- Hellmut Merkle
- Melanie Falgairolle
- Michael James O'Donovan
- Dvir Blivis
- Dave Ide
National Institute of Mental Health (IRP)
- Dave Ide
National Heart, Lung, and Blood Institute (IRP)
- Nima S Ghorashi
The funders had no role in study design, data collection and interpretation, or the decision to submit the work for publication.
Ethics
Animal experimentation: All experiments were carried out in compliance with the National Institute of Neurological Disorders and Stroke Animal Care and Use Committee (Animal Protocol Number 1267-18).
Copyright
This is an open-access article, free of all copyright, and may be freely reproduced, distributed, transmitted, modified, built upon, or otherwise used by anyone for any lawful purpose. The work is made available under the Creative Commons CC0 public domain dedication.
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Magnetic resonance measurements of cellular and sub-cellular membrane structures in live and fixed neural tissue
eLife 8:e51101.
https://doi.org/10.7554/eLife.51101
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