Nitric Oxide And Erectile Dysfunction
Nitric oxide is a molecule that is produced inside the walls of your blood vessels.
And this nitric oxide is essential in order for you to get an erection.
Because in order to get an erection, your penis needs to fill with blood. Nitric oxide is the gatekeeper that enables the blood vessels to open up, so that blood can flow into your penis.
When your penis is filled with blood and the blood pressure inside your penis has increased sufficiently, you have an erection.
Therefore, you need adequate nitric oxide production to get and maintain erections. With insufficient nitric oxide, you are more likely to struggle with erectile dysfunction.
Let’s explore this link between nitric oxide and erectile dysfunction in more detail.
The Link Between Nitric Oxide And Erectile Dysfunction
Nitric oxide is a simple molecule, consisting of one atom of nitrogen and one atom of oxygen.
In the medical field, little attention was given to this substance until the 1970’s.
But this changed in the 1970’s, when researchers discovered that nitric oxide could dilate blood vessels.
Meaning that it could expand blood vessels, so that more blood could flow through the blood vessels.
And it was also discovered that this nitric oxide is incredibly important in order for you to get erections. And therefore also to avoid erectile dysfunction.
Let me explain:
The inside of your blood vessels are lined by something called endothelial cells. These cells act as selective filters that regulate the passage of gases, fluids and other matter across their membranes.
But not only that, these endothelial cells are also instrumental in the production of the signalling molecule and free radical, nitric oxide.
Within these endothelial cells sit enzymes called nitric oxide synthase. And these are what produce the nitric oxide.
These nitric oxide synthase enzymes steal a nitrogen atom from something called L-arginine, combine it with an oxygen atom, and voila! Nitric oxide was just made.
OK, but how does this nitric oxide enable blood vessels to expand?
Let’s start from the very beginning:
A blood vessel is a tube that transports blood. This tube also consists of many layers (see illustration below). One of these layers is made of a muscle called smooth muscle.
These smooth muscles can expand and contract, and can by doing so, increase or decrease the bloodflow through the blood vessels.
The smooth muscles that surround the blood vessels in your penis are normally in a state of contraction.
Meaning, they squeeze around the blood vessels so that practically all the blood is forced out.
A flaccid penis.
However, this all changes when nitric oxide is manufactured.
When nitric oxide is formed in the endothelium in the blood vessels of your penis, it is then diffused into your smooth muscles.
And when these muscles are infused with nitric oxide, something very important happens:
The muscles stop the contraction – they start to relax!
And when the smooth muscles relax, the blood vessels open up. And blood surges into your penis.
Now that blood flows into your penis, your penis fills up and starts to become erect.
That is how nitric oxide is fundamental and necessary in order for you to get erections. And also, how you will normally struggle with erectile dysfunction if you don’t produce enough nitric oxide.
But Your Body Can Also Manufacture Nitric Oxide In A Different Way
Your digestive system can also produce nitric oxide.
This happens when you consume foods high in nitrates, such as leafy greens or beetroot.
Then a certain bacteria that is normally present on the back of your tongue gets to work.
For this bacteria, the nitrate is food. It uses the nitrate as energy.
And in the process of using nitrate to make energy, the bacteria utilize a nitrate reducing enzyme called nitrate reductase, to generate nitrite from nitrate.
Once this nitrite is in your stomach, gastric acids convert it to three different substances:
Nitric oxide, nitrogen dioxide and dinitrogen trioxide.
Therefore, your body can produce nitric oxide in a different way. Without using nitric oxide synthase.
However, nitric oxide is a very unstable molecule (more about this below), and therefore almost immediately converts to other substances.
However this is not bad news. Because these new substances can be stored, and can be re-converted to nitric oxide as and when you need it.
Nitric Oxide And Viagra
In the late 1970s, researchers who were investigating the dilation mechanisms of the anti-angina drug nitroglycerine, made a very interesting discovery.
By the way, angina is chest pain that occurs when your heart doesn’t get enough oxygen-rich blood.
When this nitroglycerine was administered to angina patients, it reacted with other substances in the body and subsequently converted into nitric oxide.
And researchers discovered that this nitric oxide produced potent vasodilation of the blood vessels.
This finding then initiated a whole new raft of research into nitric oxide.
And then came a chance discovery that changed the medical world forever:
In the late 1980s, as nitroglycerine was given to angina patients, many of these patients experienced a rather peculiar side effect:
A large number of the angina patients got firm and long-lasting erections from the angina drug.
In fact, this experimental drug was far better at giving patients erections, than treating the angina.
What the researchers discovered, was that nitric oxide induced relaxation of the smooth muscles in the penis, which again caused increased bloodflow, and hence erections.
This lead to the development of the erectile dysfunction drug Viagra in 1989.
However, it was not approved for use to treat erectile dysfunction by the FDA in the U.S. until 1998.
As a result, in 1998, three scientists received the Nobel Prize in Physiology for their discoveries of “nitric oxide as a signalling molecule in the cardiovascular system.”
Nitric oxide was also named the molecule of the year in 1992.
A Last Few Words About Nitric Oxide
Nitric oxide is what is called a free radical because it contains a single unpaired electron in its molecule.
Hence it is very reactive, and has a half-life of only a few seconds.
It is therefore normally not present in the body as nitric oxide, but reacts with other molecules to form more stable components such as nitrate.
So when nitric oxide is created somewhere in the body, it has an almost immediate effect because of this very reactive property.
At the same time, unless there is an adequate and persistent supply of nitric oxide, the impact will wane quickly.
But nitric oxide isn’t just essential for your erections. It is also paramount for a large number of other critical tasks in your body.
Some of these other important roles of nitric oxide are:
- It acts as a potent vasodilator that relaxes the arteries. Therefore, nitric oxide plays a critical role in regulating blood pressure and overall circulation, as well as helping the delivery of nutrients and oxygen to every system, organ, and tissue in the body.
- During physical exercise, nitric oxide is produced by the endothelial cells in order to dilate the arteries. This enables bloodflow to increase, and hence the muscles and other tissues are supplied with the increased amounts of oxygen and nutrients they need.
- Nitric oxide acts as a neurotransmitter in the brain, and is especially important in regards to learning and memory.
- Nitric oxide improves brain functioning and reduces cognitive decline.
- Nitric oxide is important to the immune system as white blood cells use nitric oxide to fight off bacteria, parasites and viruses. Nitric oxide produced by white blood cells is toxic to these entities and therefore plays an important role in their destruction.
- Nitric oxide plays an important role in bone formation and remodeling of old and damaged bones. Nitric oxide is utilized by cells called osteoblasts, to maintain and grow bones.
- A wide range of cellular activity is regulated by nitric oxide, including cell division, cell survival and cell movement.
- Nitric oxide facilitates sleep and particularly REM sleep, and it also improves sleep recovery. Sleep apnea syndrome is correlated with decreased levels of nitric oxide.
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