Banked Blood May Lose Key Gas

Loss May Make It Harder for Banked Blood to Deliver Oxygen to Tissues

From the WebMD Archives

Oct. 9, 2007 -- Banked blood quickly loses a gas that's needed to deliver oxygen to tissues, new research shows.

The gas is called nitric oxide.In two new studies, scientists report that when blood is stored under normal conditions, nitric oxide's ability to do its job fades rapidly.

Treating banked blood with nitric oxide may fix that problem, according to the researchers, who included Duke University's Jonathan Stamler, MD.

"This data is of considerable interest," the American Red Cross tells WebMD. "We anticipate it may eventually lead to a better understanding of how to preserve red cell properties during storage."

In lab tests, Stamler's team tested banked blood's ability to deliver oxygen to heart tissue in dogs.

The researchers focused on SNO-Hb (S-nitrosohemoglobin), which is the blood protein hemoglobin tweaked by nitric oxide.

Banked blood was better at delivering oxygen to heart tissue in dogs when the blood had been treated with nitric oxide, compared with banked blood lacking SNO-Hb.

In other experiments, another team of researchers -- including Duke University's Timothy McMahon, MD, PhD -- found that red blood cells in banked blood lost some of their flexibility in storage. That process happened more slowly than SNO-Hb loss in banked blood.

Red blood cells need to be flexible to travel through tiny blood vessels; otherwise, they could block or take longer to navigate through those blood vessels, McMahon's team notes.

Replenishing SNO-Hb may help keep stored red blood cells flexible, according to McMahon and colleagues.

Both studies were partly funded by Nitrox/N30, a company which is developing ways to treat oxygen delivery disorders. Several of the researchers report financial ties to Nitrox/N30, and McMahon is the co-inventor of a patent related to red blood cells and SNO gases.

WebMD Health News Reviewed by Louise Chang, MD on October 09, 2007

Sources

SOURCES: Reynolds, J. Proceedings of the National Academy of Sciences, Oct. 8-12, 2007; early online edition. Bennett-Guerrero, E. Proceedings of the National Academy of Sciences, Oct. 8-12, 2007. News release, Duke University Medical Center. News release, Proceedings of the National Academy of Sciences. American Red Cross.

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