The research was conducted at the CWM with a Jefferson Lab and CWM-built medical imaging system to perform investigational studies of mice. Bob Welsh, a JLab/CWM jointly appointed professor, is one researcher working on the project. The research demonstrates that scientists can learn about how the body uses certain substances of interest - such as insulin, the fat-regulating protein leptin and a wide range of other biological compounds - by tracking how these substances move through the body of a mouse.
"The way we follow those substances is to attach to them a radioactive isotope of iodine, Iodine-125. Iodine-125 emits a low-energy gamma ray," Welsh says, "It's not a tremendous amount of energy, but it's easy to track with these very precise detectors that have been designed and built by the Jefferson Lab Detector Group."
The thyroid needs iodine to regulate metabolism and is unable to distinguish between regular dietary iodine and ingested radioactive iodine. So the researchers weren't surprised when, in the course of the project, they noticed that the mice subjects' thyroids always absorbed a significant amount of radioactive iodine. In addition to being potentially bad for the mouse, the thyroid's absorption of radioactive iodine made the images difficult to interpret and could provide false-positive readings or possibly obscure substantial iodine uptake in nearby tissues.
The team decided to test what would happen if they gave the mice potassium iodide, the FDA-recommended drug for blocki
Contact: Kandice Carter
DOE/Thomas Jefferson National Accelerator Facility