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美国科学家最新的一项研究发现，老鼠体内排出的带有臭鸡蛋气味的难闻气体能够控制它们体内的血压。这种令人生厌的气体叫做硫化氢。细菌在人的结肠内也会排出这种气体并最终以人放屁的形式将其排出体外，该过程与老鼠极为相似。由此，研究人员就可以尝试研究出一种能够促进硫化氢形成的治疗方法来替代现有的治疗高血压的方法。
A smelly rotten-egg gas in farts controls blood pressure in mice, a new study finds.
A smelly rotten-egg gas in farts controls blood pressure in mice, a new study finds.
The unpleasant aroma of the gas, called hydrogen sulfide (H2S), can be a little too familiar, as it is expelled by bacteria living in the human colon and eventually makes its way, well, out.
The new research found that cells lining mice's blood vessels naturally make the gas and this action can help keep the rodents' blood pressure low by relaxing the blood vessels to prevent hypertension (high blood pressure). This gas is "no doubt" produced in cells lining human blood vessels too, the researchers said.
"Now that we know hydrogen sulfide's role in regulating blood pressure, it may be possible to design drug therapies that enhance its formation as an alternative to the current methods of treatment for hypertension," said Johns Hopkins neuroscientist Solomon H. Snyder, M.D., a co-author of the study detailed in the Oct. 24th issue of the journal Science.
Snyder and his colleagues compared normal mice to mice that were missing a gene for an enzyme known as CSE, long suspected as being responsible for making hydrogen sulfide. As they measured hydrogen sulfide levels taken from tissues of the CSE-deficient mice, the scientists found that the gas was depleted in the cardiovascular systems of the altered mice. By contrast, normal mice had higher levels of the gas, thereby showing that hydrogen sulfide is naturally made by mammalian tissues using CSE.
Next, the mice were subjected to higher blood pressures comparable to serious hypertension in humans. Scientists had them respond to a chemical called methacholine that relaxes normal blood vessels. The blood vessels of the CSE-lacking mice hardly relaxed, indicating that hydrogen sulfide is a huge contender for regulating blood pressure.
Hydrogen sulfide is the most recently discovered member of a family of gasotransmitters, small molecules inside our bodies with important physiological functions.
This study is the first to reveal that the CSE enzyme that triggers hydrogen sulfide is activated itself in the same way as other enzymes when they trigger their respective gasotransmitter, such as a nitric oxide-forming enzyme that also regulates blood pressure, Dr. Snyder said.
Because gasotransmitters are common in mammals all over the evolutionary tree, these findings on the importance of hydrogen sulfide are thought to have broad applications to human diseases, such as diabetes and neurodegenerative diseases.
The research was supported by grants from the U.S. Public Health Service and the Canadian Institutes of Health Research as well as a Research Scientist Award.
