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Comparison of hypothalamic mRNA levels in mice euthanized by CO2 inhalation and focused-beam microwave irradiation

Lab Animal volume 40, pages 313–318 (2011)Cite this article

Abstract

Focused-beam microwave irradiation (FBMI) is a relatively new method for euthanasia of small mammals and is available to most researchers. Compared with CO2 inhalation, this method of euthanasia has the advantage of preserving fast-degrading metabolites. But differences in brain RNA quantity and quality, gene expression and histology in mice euthanized by CO2 inhalation versus FBMI have not been investigated. Here the authors report that a smaller quantity of RNA was isolated from brains of mice euthanized by FBMI compared with those of mice euthanized by CO2 inhalation. They also found relative differences in the levels of the expression of some genes. These studies suggest that either method can be used for histological analysis or RNA isolation, but the authors caution against combining the techniques within a single study on gene expression.

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Figure 1: The microwave animal fixation system.
Figure 2: Gross histological analysis of brain tissue.
Figure 3: RNA quantity and quality.
Figure 4: Hypothalamic expression of Nhlh2 and Pcsk1 mRNA in mice euthanized by CO2 inhalation or FBMI.
Figure 5: Hypothalamic expression of Pomc mRNA in mice euthanized by CO2 inhalation or FBMI.
Figure 6: Hypothalamic expression of Mc4r and Trh mRNA in mice euthanized by CO2 inhalation or FBMI.

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  1. Human Nutrition, Foods and Exercise, Virginia Polytechnic Institute and State University, Blacksburg, VA

    Haiyan Zhang &  Deborah J. Good

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Correspondence to Deborah J. Good.

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Zhang, H., Good, D. Comparison of hypothalamic mRNA levels in mice euthanized by CO2 inhalation and focused-beam microwave irradiation. Lab Anim 40, 313–318 (2011). https://doi.org/10.1038/laban1011-313

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