Nitric oxide disables pain crises of sickle cell disease

A new study has suggested that nitric oxide gas directly impacts the source of the classic, disabling pain crises of sickle cell disease.

The short-acting gas helps unglue hemoglobin molecules that stick together, forming long chains that ultimately deform red blood cells and prompting a cellular pileup in small blood vessels and pain, said C. Alvin Head, Chairman of GHSU’s Department of Anesthesiology.

The findings get scientists closer to understanding why red blood cells sickle and potentially to an easy-to-use, non-addictive treatment that helps avoid it, said Tohru Ikuta, GHSU molecular hematologist.

The study of 18 patients showed that the half who inhaled nitric oxide for four hours had better pain control than those receiving only the standard self-administered morphine.

The new study examined nitric oxide’s impact from many angles and showed that it appears to disperse dense, solid chains of hemoglobin troublemakers.

Once a significant number of hemoglobin molecules stick together, it causes red blood cells to distort from their natural round shape that easily maneuvers blood vessels to a sickle-shape. At that point, red blood cells also become uncharacteristically sticky.

They found nitric oxide reduced the length of the unnatural hemoglobin strands, made the strands more fragile and, using a high-powered confocal microscope, they could see it also helped cells regain a more normal shape. Studies were done on human cells in vitro.

The study has been published in the American Journal of Hematology.Get PDF (114K)

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