Erectile dysfunction

Erectile dysfunction

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much more. Try it free today! In erectile dysfunction, an individual is
unable to develop or maintain an erection during sex. This disorder is also called impotence and
like other sexual dysfunction, this condition becomes more common with age. Sex can be important within relationships,
so erectile dysfunction often carries with it emotional and psychological stigma. In both males and females, sexual activity
involves a sequence of events called the sexual response cycle. This cycle has four phases, excitement, plateau,
orgasm, and resolution. During the excitement phase, muscle tension,
heart rate, and blood flow to the genitals increases. In males, this is called an erection. When these reach the maximum level, it’s
called the plateau phase. Next, the accumulated sexual tension gets
released during orgasm, causing ejaculation in males. Immediately after orgasm comes the resolution
phase, where the body slowly returns to its original, un-excited state. Alright, let’s take a closer look at the
penis which is made of three long cylindrical bodies: the corpus spongiosum that surrounds
the penile urethra, and the two corpora cavernosa made of erectile tissue. The corpora cavernosa are wrapped in a fibrous
coat called the tunica albuginea, and each corpus cavernosum is made up of blood-filled
spaces called the cavernosal spaces. These areas are lined with endothelial cells
surrounded by smooth muscle. Running down the centre of each corpus cavernosum
is a large artery called the deep artery which gives off smaller arteries that supply the
cavernosal spaces. Next, blood get drained from these spaces
by small emissary veins, which drain into the deep dorsal vein. This vein then carries the blood back into
the systemic circulation. Now, the penis receives both somatic and autonomic
innervation through the cavernous nerves, which innervate both the corpus spongiosum,
and the corpora cavernosa. You can remember the functions of these fibers
with the mnemonic “point and shoot.” “Point” is erection and it’s caused
by “P,” or parasympathetic fibers. “Shoot” is ejaculation and the “S”
is for sympathetic. Now, an erection can happen in two ways, either
by physical stimulation of the penis or genitals, called reflex erection, or by becoming emotionally
stimulated by a thought, called psychogenic erection. In both cases, the parasympathetic nerve fibers
in the cavernosal spaces release acetylcholine from their nerve endings. The acetylcholine bind to muscarinic receptors
on endothelial cells, which activates the enzyme nitric oxide synthase. Nitric oxide synthase converts the amino acid
arginine into citrulline and nitric oxide. The nitric oxide diffuses into the nearby
smooth muscle cells, and activates guanylate cyclase, which converts GTP molecules to cGMP. This leads to a fall in intracellular calcium
levels causing the smooth muscles to relax, and allowing the cavernosal spaces to expand
and fill with blood. The corpora cavernosa grow in size, and compress
the veins, making it harder for blood to leave. With more blood coming in but very little
blood leaving, the penis can maintain an erection. Erectile dysfunction leads to an inability
to develop and maintain a full erection. Causes include psychological ones like stress,
performance anxiety, and depression. In addition, there are a number of physiologic
causes as well. The most common physiologic cause for erectile
dysfunction is an inadequate blood supply due to atherosclerosis and blood vessel damage
from hypertension. Atherosclerosis is caused by the buildup of
atheromatous plaques that can harden the arteries supplying the penis, which makes it difficult
for them to dilate. Hypertension causes wear and tear in the endothelial
cells, and decrease their ability to produce nitric oxide. Another condition that can also damage the
arteries is diabetes mellitus. High glucose levels can cause hyaline arteriolosclerosis
in the small arterioles in the penis. This is where the arteriole walls develop
hyaline deposits, which makes it harder for them to dilate. It also builds up in the capillaries causing
the basement membrane to thicken which makes it harder for oxygen to efficiently move from
the vascular space to the tissues, causing hypoxia and death of the smooth muscle cells. This hypoxia also causes the parasympathetic
nerve fibers to die off. Damaged parasympathetic nerve fibers can’t
release acetylcholine, so there’s less nitric oxide synthase activation, and less nitric
oxide is produced. Also, conditions like stroke, multiple sclerosis,
and back or pelvic trauma can directly damage the nerves, leading to erectile dysfunction. Next, endocrine dysfunctions that causes testosterone
levels to fall, like hypogonadism, can cause erectile dysfunction. This happens because low testosterone levels
are associated with lower levels of nitric oxide synthase, which causes less nitric oxide
to be produced, and less smooth muscle relaxation. Since testosterone production decreases with
age, it’s normal for erections to become more difficult to achieve and maintain later
in life. Finally, many medications can cause erectile
dysfunction as a side effect. These include diuretics because they leave
less fluid in your circulation, making it difficult to achieve an erection, and medications
like antidepressants and methadone, but those mechanisms are not as well understood. There is no specific test to diagnose erectile
dysfunction, so the diagnosis largely relies on the sexual experiences of the individual. Careful questioning of psychological stressors
as well as blood tests to check for testosterone and glucose levels, a neurological assessment,
and duplex ultrasound to evaluate blood flow and atherosclerosis can be done to investigate
the cause of erectile dysfunction. Treatment of erectile dysfunction largely
focuses on addressing the underlying cause. In terms of medications, PDE-5 inhibitors,
like sildenafil can be used. These medications inhibit the PDE-5 enzyme
in endothelial cells which normally breaks down cGMP, leading to higher levels of cGMP. That allows for more smooth muscle relaxation
which facilitates an erection. Sometimes, vacuum erection devices can be
used. These devices apply negative pressure around
the penis which can help draw in blood to achieve an erection. Finally, surgical procedures like prosthetic
implants can be embedded into the penis. They does not cause erections but it could
help keep the penis rigid. All right, as a quick recap, erectile dysfunction
is the inability to develop or maintain an erection and it could have psychological or
organic causes. Organic causes can be due to cardiovascular
disorders like hypertension, neurological problems like those caused by diabetes, or
hormonal dysfunction where testosterone levels decrease. Various medications, like diuretics can also
cause erectile dysfunction as an side effect. There’s no specific test to diagnose erectile
dysfunction, so, diagnosis is typically geared at detecting pre-existing causes. Treatment includes PDE-5 inhibitors like sildenafil,
vacuum erection devices, and surgery.

27 Replies to “Erectile dysfunction”

  1. Also do a detailed video on "Masturbation". There are so much of myths out there on internet about this topic. It would be highly appreciated if you include all topics related to masturbation. Thanks in advance.

  2. By all the looks of it, you may have as well read about this kind of stuff in Greyzar Drinbo's internet site, right? It's super strong, and does not even matter if you think you could have the most detrimental case of PE in history. You can start today and maybe start seeing measurable results within the week.

  3. Oral phentolamine mesylate (brand names Vasomax, Vigamed) is an excellent ED drug that should be widely available. Phentolamine is not a PDE-5 inhibitor (e.g. Viagra), it is an alpha blocker that prevents sympathetic action in the penis, thus improving blood flow and erections. It is an approved ED treatment in several countries and there are several studies that show its efficacy.

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