The effect of soft X-radiation on myofibrils
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Updated: Nov 8, 2026

X-ray Diffraction of Intact Murine Skeletal Muscle as a Tool for Studying the Structural Basis of Muscle Disease
Published on: July 18, 2019
P M Bennett1, G F Foster, C J Buckley
1MRC Muscle and Cell Motility Unit, Randall Institute, King's College London, U.K.
Abstract:
Myofibrils, the contractile organelles from striated muscles, have been examined in the X-ray microscope to determine the effect of radiation on their function and structure. Using X-rays of energy 350-385 eV in the water window we find that after an exposure to 7.5 x 10(5) photons/micron2 (calculated to give an absorbed dose of 20,000 Gy) the myofibrils will no longer contract. The use of the free radical scavenging agent, DMSO, gives some protection to the fibrils. It has also been found that after this much irradiation the fibrils lose up to 20% of their mass. Further substantial mass loss occurs on subsequent irradiation. After 25 times the loss-of-function exposure only 30% of the mass remains. Analysis of a series of images of the same myofibril covering this range of exposures shows that the mass is preferentially lost in some areas of the structure and consequently significant structural changes occur.
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