Protocol for high-power, brain-focused microwave fixation to define rodent metabolism

Alex R Cantrell; Tara R Hawkinson; Jelena A Juras; Madison B Webb; Terrymar Medina; Roberto A Ribas; James Collins; Amelia A Bunnell; Lyndsay E A Young; Kia H Markussen; Douglas A Andres; Joanna R Long; Craig W Vander Kooi; Bret N Smith; Ramon C Sun; Matthew S Gentry

doi:10.1016/j.xpro.2025.103794

Protocol for high-power, brain-focused microwave fixation to define rodent metabolism

STAR Protoc. 2025 Jun 20;6(2):103794. doi: 10.1016/j.xpro.2025.103794. Epub 2025 Apr 25.

Authors

Alex R Cantrell¹, Tara R Hawkinson¹, Jelena A Juras², Madison B Webb², Terrymar Medina¹, Roberto A Ribas³, James Collins¹, Amelia A Bunnell¹, Lyndsay E A Young⁴, Kia H Markussen², Douglas A Andres², Joanna R Long¹, Craig W Vander Kooi¹, Bret N Smith³, Ramon C Sun⁵, Matthew S Gentry⁶

Affiliations

¹ Department of Biochemistry and Molecular Biology, University of Florida, College of Medicine, Gainesville, FL 32610, USA.
² Department of Molecular and Cellular Biochemistry, University of Kentucky, College of Medicine, Lexington, KY 40536, USA.
³ Department of Biomedical Sciences, Colorado State University, Fort Collins, CO 80523, USA.
⁴ Department of Cell and Molecular Pharmacology and Experimental Therapeutics, Medical University of South Carolina, Charlston, SC 29425, USA.
⁵ Department of Biochemistry and Molecular Biology, University of Florida, College of Medicine, Gainesville, FL 32610, USA; Center for Advanced Spatial Biomolecule Research, University of Florida, College of Medicine, Gainesville, FL 32610, USA. Electronic address: ramonsun@ufl.edu.
⁶ Department of Biochemistry and Molecular Biology, University of Florida, College of Medicine, Gainesville, FL 32610, USA; Center for Advanced Spatial Biomolecule Research, University of Florida, College of Medicine, Gainesville, FL 32610, USA. Electronic address: matthew.gentry@ufl.edu.

Abstract

Analysis of metabolites provides key insights into brain physiology and function. Due to post-mortem metabolism, both the euthanasia method and dissection time can make a critical difference. Here, we describe a protocol to euthanize rodents by microwave irradiation. This workflow details steps for animal placement, tissue fixation, and post-fixation processing. This protocol enables the rapid halting of metabolic activity for the accurate assessment of the metabolome in situ for analyses such as mass spectrometry and nuclear magnetic resonance. For complete details on the use and execution of this protocol, please refer to Juras et al.¹.

Keywords: metabolism; metabolomics; neuroscience.

MeSH terms

Animals
Brain* / metabolism
Mass Spectrometry
Metabolome
Metabolomics* / methods
Mice
Microwaves*
Rats
Tissue Fixation* / methods

Abstract

MeSH terms

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