Answer: technetium-99.
Step-by-step explanation:
This is not an answer that you can look for in a book.
You need to do some research.
You can fiind the abstract of the article titled Molecular imaging of atherosclerosis using a technetium-99m-labeled endothelin derivative.
The conclusion of this scientific article is that labeling with the radiosotope Tc - 99 iis feasibele to visualize the effects of an experiment inducing atherosclerosis, which gives the answer to the question posted.
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