Detecting Hs in Vivo

DESPITE HIGH HURDLES, scientists are making significant progress in developing ways to better measure concentrations of a tiny molecule that could prove as important as nitric oxide in helping to control cellular activities in living organisms. Like NO, hydrogen sulfide plays an important role in cell signaling. H 2 S mediates a number of biological processes, including blood pressure, metabolic rate, angiogenesis, and anti-inflammatory effects. Sulfide levels are also altered in conditions like Alzheimer’s disease and diabetes. The ability to measure these levels could be useful diagnostically. Researchers would love to learn more about how H 2 S works in the body. But that task has proven difficult because basic tools to measure H 2 S concentrations selectively and sensitively in tissue and blood, ideally in real time, have been lacking. It’s difficult to develop probe molecules that are selective for in vivo H 2 S signaling because cells and tissues contain thiols, sulfenic acids, and sulfites that can compete with H 2 S for ...