Corpus: Ejaculatory duct

The ejaculatory duct is a part of the male genital tract. It arises from the connection of the vas deferens (ductus deferens) with the excretory duct of the vesicle gland (ductus excretorius).

The two ejaculatory ducts run for the most part within the prostate (approx. 2 cm long). They open on the colliculus seminalis (seminal mound) into the pars prostatica of the urethra (urethra). During ejaculation, the ducts guide the sperm and the secretion of the vesicle gland into the urethra for further transport.

The ejaculatory duct is lined with mucosa, which is laid in delicate longitudinal folds and has a single-layered, highly prismatic epithelium. A sphincter mechanism is found at the urethral opening, which has the task of preventing the retrograde penetration of urine into the vesicle gland. This is achieved by a combination of small veins, elastic fibres and smooth muscle cells. Special longitudinal muscle fibres of the urethra are responsible for opening the ejaculatory duct. Closure, on the other hand, is controlled by the tension of the vesicoprostatic muscle. Under the influence of the sympathetic nervous system, the sphincter mechanism relaxes during ejaculation, while the parasympathetic nervous system is responsible for sphincter closure.

During surgical treatment (TUR-P) of benign prostatic hyperplasia (BPH), the muscles of the ejaculatory duct can be destroyed, which in some cases leads to the phenomenon of retrograde ejaculation.