Will hydrogen sulfide help with erectile dysfunction?

An erection occurs from rotten eggsVladimir Gram, "Newspaper.

Ru»Hydrogen sulfide has recently joined NO and CO gases in the list of blood pressure regulators.

But on the basis of this "smelly" signaling system, a "new Viagra" may appear. The patent for the "old viagra", which is based on NO, will end in the coming years.

The discovery of the role of nitric oxide in regulating blood pressure was awarded the Nobel Prize in Physiology or Medicine in 1998. Although nitroglycerin was used to counteract cardiovascular diseases much earlier, it was only thanks to the work of the 1998 Nobel Laureates and their colleagues that it became clear why it works. In fact, NO, whose biological effect has long been reduced to the formulation "toxic gas", turned out to be a "gaseous hormone", a molecular transmitter of intracellular signals. It promotes relaxation of smooth muscles due to the release of cyclic guanosine monophosphate (cGMP), and since smooth muscles line the walls of our vessels, its relaxation in most cases helps to reduce pressure and increase blood flow.

Although there are a great many drugs that exploit the NO-cGMP signaling cascade, none of them can even compare their fame with sildenafil, better known under its trademark "Viagra". Sildenafil interferes with the enzyme that destroys cGMP in the cavernous body of the penis. Since nitric oxide, meanwhile, continues to stimulate the release of cGMP, the smooth muscles remain relaxed, the vessels are dilated, and the penis is ready for use. And so for several hours, until sildenafil is destroyed and removed from the body (or until the excitement subsides – without an external start of the NO-cGMP cascade, the "blue pill" will not work).

Coincidentally or not, the Nobel Prize "for NO" was given in the same year in which "Viagra" began to be sold in the United States.

It was already 11 years ago, and very soon, in 2011-2013, Pfizer will run out of a patent for the production of this most popular remedy. It's time to think about something new, suitable for patenting, to look for new means to increase blood flow in cavernous bodies.

In recent years, two more "poisonous gases" have joined the number of "gaseous hormones" - CO, or carbon monoxide, and a gas with an even less noble reputation – hydrogen sulfide, H ₂ S. At first, scientists noticed that the lack of an enzyme that produces hydrogen sulfide leads to an increase in blood pressure, and then directly showed that the direct introduction of non-toxic doses of hydrogen sulfide into the body can lower the pressure by no less than 30%.

Against the background of such results, it seems more than natural to study Italian and American scientists who decided to check how hydrogen sulfide, which has the smell of rotten eggs, affects erectile function. Among the authors of the work, the results of which are published in the latest issue of the Proceedings of the National Academy of Sciences, and the 1998 Nobel laureate Luis Ignarro from the University of California, Los Angeles.

The human body synthesizes hydrogen sulfide from the amino acid L-cysteine using two enzymes – cystathionine-β-synthase and cystathionine-γ-lyase. It was by influencing the latter that scientists at one time proved the influence of "smelly gas" on pressure. Therefore, Ignarro and his colleagues began their work by making sure that there were two enzymes in the cavernous body itself.

The scientists worked with human biomaterial – thinly sliced cavernous bodies extracted during sex reassignment operations. There is enough of this good in the University of California clinic, so the results obtained during the study are directly applicable to humans.

As it turned out, the smooth muscles are full of both of these enzymes, although almost exclusively gammaliasis is found in the nerve endings that match it. Moreover, these enzymes work – when a cavernous body preparation ground into a pulp was added to L-cysteine, the rate of H2S synthesis increased threefold.

But the main test, of course, was the reaction of cavernous bodies to an increase in the concentration of hydrogen sulfide itself in thin strips of the cavernous body. Scientists increased it by injecting L-cysteine into the drug, from which H2S enzymes are produced, and sodium hydrosulfide (NaHS), which reacts with water without any enzymes with the release of hydrogen sulfide.

As Ignarro and his colleagues have shown, non–toxic doses of gas lead to immediate relaxation of smooth muscles - the greater the dose. And if this cavernous body were not cut on the object table, but whole in the penis, it would immediately mean increased blood flow and a strong erection.

Moreover, experiments on immobilized rats have shown that injection – both NaHS and L-cysteine – directly into the cavernous body causes an immediate erection, and again the greater and longer the greater the dose of hydrogen sulfide that has reached smooth muscles. For example, 10 micrograms of NaHS per 200-gram rat was enough to keep an erection in a rodent under anesthesia for about half an hour. At 30 micrograms, it turned out to be something about an hour, at 100 micrograms - an hour and a half. The injection of L-cysteine acted in approximately the same way and in the same doses. But once the cysteine-gamma-lyase was blocked with the help of propargylglycine, the effect disappeared.

So the "smelly" signal path has every chance of becoming the road to the "new viagra". But this does not mean that it will be easy to find her. Sildenafil works precisely according to the variant of the enzyme that destroys dilating cGMP vessels in the cavernous body, and is much less effective against cGMP destroyers in other smooth muscles of the body. If sildenafil did not have such specificity, so when taking Viagra, the vessels would expand throughout the body, and there would simply not be enough blood for an erection. Before the "hydrogen sulfide viagra" appears, it is necessary to understand the peculiarities of hydrogen sulfide metabolism specifically in the penis.

And even after reading this note, you should not think that men suffering from gas have any advantage in sexual terms. The hydrogen sulfide that fills the digestive system is synthesized by bacteria that have nothing to do with regulating the tone of smooth muscles – especially in the penis.

Portal "Eternal youth" www.vechnayamolodost.ru10.03.2009