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Updated: Aug 18, 2026

Analysis of the Mitochondrial Density and Longitudinal Distribution in Rat Live-Skeletal Muscle Fibers by Confocal Microscopy
10:53

Analysis of the Mitochondrial Density and Longitudinal Distribution in Rat Live-Skeletal Muscle Fibers by Confocal Microscopy

Published on: December 1, 2023

Ultrastructural differences in mitochondria of skeletal muscle in the prerigor and rigor states

P V Hegarty, K J Dahlin, E S Benson

    Experientia
    |August 15, 1978
    PubMed

    Insights

    Mitochondrial changes in skeletal muscle, including loss of cristae and matrix, precede myofibrillar protein alterations during rigor mortis. Researchers caution that postmortem pH can influence these observed mitochondrial ultrastructural changes.

    Area of Science:

    • Mitochondrial biology
    • Skeletal muscle physiology
    • Postmortem changes

    Background:

    • Rigor mortis involves complex biochemical and structural alterations in muscle tissue.
    • Mitochondria play a crucial role in cellular energy metabolism and are susceptible to postmortem degradation.

    Purpose of the Study:

    • To investigate the early ultrastructural changes in skeletal muscle mitochondria during rigor mortis.
    • To differentiate mitochondrial alterations caused by rigor mortis from those induced by trauma or pH changes.

    Main Methods:

    • Transmission electron microscopy was used to examine mitochondrial ultrastructure in skeletal muscle.
    • Analysis focused on cristae integrity, matrix density, and overall mitochondrial morphology.

    Main Results:

    • Loss of mitochondrial cristae and matrix density were observed in skeletal muscle mitochondria.
    • These mitochondrial changes occurred before detectable alterations in myofibrillar proteins.

    Conclusions:

    • Mitochondrial degradation is an early event in the development of rigor mortis.
    • Postmortem pH and trauma must be carefully considered when interpreting mitochondrial ultrastructural findings in muscle tissue.

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