Scientists have provided relief to thousands of men who suffer from priapism, or the condition that causes prolonged erection even without an arousal, by identifying the biochemical basis of the disorder.
In a study on male mice, researchers at the University of Texas Medical School at Houston found that raised levels of the biochemical adenosine, which can cause blood vessels to dilate and has the potential to influence blood flow into the penis, was the cause behind priapism.
To test the idea, the researchers used mice genetically transformed to lack an enzyme that breaks down adenosine and as a result leads to very high adenosine levels.
After the experiment, the team found that the mice experienced constant erections.
However, the condition quickly settled when the animals were given a chemical called polyethylene glycol-ADA that decreases but does not eliminate adenosine.
"There are tremendous clinical implications. We hope this might lead to adenosine-blocking treatment that will prove very effective," New Scientists magazine quoted lead author Yang Xia, as saying.
However, she added that more studies are required to see if increased adenosine levels also cause the much rarer female priapism, in which the clitoris becomes swollen.
She pointed out that safety concerns behind using polyethylene glycol-ADA should not arise, as it has already been licensed to treat children with a similar, rare enzyme deficiency.
"So safety should not be an issue," she said.
Xia said that her team is hoping trials on male priapism sufferers will begin this year.
Nick Robson, a biochemist at Newcastle University, UK, who specialises in urological problems, says the research is a real advance.
"This exciting finding opens up the possibility of therapeutic intervention for this potentially embarrassing medical condition by blocking the receptor for adenosine," he said.
The study is published in the Journal of Clinical Investigation.