Where are the three narrowings of the male urethra?

For men, the urinary system is closely related to physical health. Although men's body structure is much better than women's, they should also pay attention to the protection of the urinary system and reproductive system. Because there are always some unexpected situations, some men will suffer from urinary system diseases, and they will suffer in the end. So where are the three narrowings of the male urethra in medicine?

The three strictures of the male urethra are located at the internal urethral opening, the membranous part and the external urethral opening.

Urethra wall tissue:

The urethral wall is composed of the mucosal layer, submucosa layer and muscle layer. On the outside of the anterior urethra, there is also the urethral cavernous body which is rich in elastic fibers and smooth muscle fibers. The urethral mucosal epithelium is transitional epithelium in the prostatic part (near the bladder), and part of it is multi-row or stratified columnar epithelium. In the part of the urethra with the urethral cavernous body, it is mainly stratified columnar epithelium, and there is also single-layer columnar epithelium on the folds. There are many circular cells in the navicular fossa in particular, and non-keratinized stratified squamous epithelium begins to appear at the distal end of the navicular fossa. The submucosa has a rich blood supply and is mainly connective tissue. The muscle layer has longitudinal muscles and external circular muscles.

Urethral glands:

Urethral glands are scattered throughout the urethra, mainly concentrated in the anterior urethral cavernous body, called paraurethral glands. During erection, they can be squeezed and secrete clear mucus to lubricate the surface of the urethral mucosa. In chronic infection, they actually secrete sticky threads. A pair of bulbourethral glands are located between the two layers of the triangular ligament, opening in the bulb of the urethra. They secrete clear and slightly gray mucus, rich in protein, and form part of the semen during ejaculation. The blood of the urethra is supplied by the internal pudendal artery and the superior vesical artery. Venous blood returns to the pudendal and perivesical venous plexus. The nerve innervation is mainly the pudendal nerve, genitofemoral nerve and sympathetic nerve.

Male urethritis:

(I) Introduction:

Male urethritis can be divided into acute urethritis and chronic urethritis.

The main symptoms of acute urethritis are excessive urethral discharge, which begins as mucus and gradually becomes purulent, as well as frequent urination, urgency, and pain when urinating.

Chronic urethritis has less secretion and mild symptoms, and some patients have no symptoms. Among sexually transmitted diseases, gonococcal urethritis is one of the main diseases, often called gonorrhea, which is caused by gonococcal infection. Another common sexually transmitted disease is non-gonococcal urethritis, which is mainly caused by chlamydia and mycoplasma infection.

The symptoms of chronic urethritis are mostly developed from acute inflammation of the anterior urethra that has not been properly treated, and the symptoms of urethritis recur or persist for more than 2 months. The patient feels that the symptoms have been alleviated, with only mild tingling and discomfort in the urethra, and the secretion has been significantly reduced. It may be combined with prostatitis, seminal vesiculitis, epididymitis, cystitis or cause urethral stenosis. Drug treatment is not easy to be thorough, and it is a mental burden or neurological symptoms appear.

(II) Causes:

1. Improper selection of drugs for the treatment of urethritis, which makes gonococci resistant to them;

2. After male urethritis is cured, secondary infection is caused by the sexual partner not receiving standardized treatment;

3. Patients with urethritis who do not take medication according to doctor's instructions and who drink alcohol or eat spicy food on a regular basis may also affect the efficacy of treatment;

4. Some patients with urethritis are only given drugs against one pathogen during treatment, ignoring the mixed infection, which eventually leads to more and more severe urethritis and no effect after multiple treatments. For example, combined with Chlamydia trachomatis or Mycoplasma infection without treatment;

5. Urethritis caused by Trichomonas;

6. Certain bacterial infections lead to non-specific urethritis;

7. Urethritis caused by ascending infection due to prostatitis that has not been cured in time;

8. Similar symptoms may also occur if urethral mucosal inflammatory damage such as edema and hyperplasia has not yet recovered, or if local nerves are stretched.