1. Gross Anatomy of Male Genital Organs
Ákos Lukáts MD.

2. Overview Components: Gonad - testis
(spermatogenesis, spermatocytogenesis, testosteron production)
Duct system – epididymis, deferent duct, ejaculatory duct
(transfer of sperm from testis to urethra for ejaculation)
Additional glands – seminal vesicle, prostate, bulbourethral glands
(produce additional components of semen)
4) Penis – transfer of semen to female genital organs

3. male sexual differentiation and behavior
Testis
Functions:
Spermatogenesis - meiosis
Spermatocytogenesis
Testosterone production
male sexual differentiation and behavior
Develops in the abdominal cavity (L2), descends to the scrotum through the inguinal canal by the 7th fetal month.
Abdomen deep inguinal ring inguinal canal superficial inguinal ring scrotum
Maldescensus testis: testis retained in the abdominal cavity or in inguinal canal. Indicates hormonal malfunction, induces sterility and increases chances of testicular tumor formation.

4. Scrotum
m. cremaster
Position in scrotum ensures a few degrees lower temperature than that of the rest of the body; a prerequisite of spermatogenesis.
Increased scrotal temperature will result in decreased fertility.
M. cremaster can pull the testis closer to pelvis increasing the temperature
Active regulation to maintain optimal level.
covering layers of testis
epididymis
appendix epididymidis
testis
appendix testis

6. Head, body, tail deferent duct
Epididymis
Head, body, tail deferent duct
Two types of duct:
Efferent ductules (10-20) in head arise from mediastinum of the testis. Highly curved tubules that transport sperm, reabsorb testicular fluid and remove the remaining residual bodies.
Ductus epididymidis in head, body and tail will continue as deferent duct. Highly muscular, curly tubes. Stores sperms, and the peristaltic movement of the muscular wall will release them during ejaculation. Also secretes several biologically active substances
Ejaculation is a result of sympathetic nerve stimulation.

7. Scrotal layers surrounding testis and epididymis
The scrotum could be regarded as a projection of the abdominal cavity.
All layers of the abdominal wall reach the scrotum as remnants making up the covering layers of testis. (including the peritoneum!)
These layers are continuous with the layers of the abdominal wall at the inguinal canal.
The testis thus maintains its original „intraabdominal” position, being surrounded by the remnants of the wall and being connected with abdominal organs via the spermatic cord. (blood supply, innervations, lymph drainage)

8. Testicular artery and vein originate from the abdominal cavity (L2) and descend to the testis in a retroperitoneal position, anteriorly crossing with the ureter. Components of the spermatic cord, thus pass within the inguinal canal. Reach the testis at the mediastinum.
Lymph of the testis is drained parallel with the artery to the retropertitoneal lymph nodes near the aorta.
Testicular tumor, which is fairly common in young males, will give its first metastases via the lymph vessels to the retroperitoneal lymph nodes and NOT to the superficial inguinal lymph nodes which is a common belief. The latter lymph node enlargement in tumor indicates that it has already penetrated the superficial scrotal layers as well.

9. Fascia of external abdominal oblique muscle
ABDOMINAL WALL
Skin
Dermis
Superficial fascia
Fascia of external abdominal oblique muscle
Internal abdominal oblique muscle
Transversus abdominis muscle
Transversalis fascia
Peritoneum
SCROTUM
Skin
Tunica dartos
External spermatic fascia (cremasteric fascia)
Cremaster muscle
Internal spermatic fascia
Tunica vaginalis testis

11. Spermatic cord
Approximately 1cm thick structure in the inguinal canal to the testis.
Contains all the structures that supply the testis and epididymis:
Deferent duct
Deferential artery
Testicular artery and vein (pampiniform plexus)
Sympathetic and parasympathetic nerves
Genital branch of genitofemoral nerve (to cremaster m.)
Ilioinguinal nerve (ext surface, to spf. layers of scrotum
Surrounded by the same layers as the testis!

12. superficial inguinal ring
Inguinal canal
deep inguinal ring
superficial inguinal ring
Borders:
Anterior: fascia of external oblique abdominal muscle
Superior: internal oblique abdominal muscle, transversus abdominis muscle
Inferior: inguinal ligament
Posterior: transversalis fascia, peritoneum
Content:
Spermatic cord in males, round ligament of the uterus in females

13. Seminal vesicle, prostate, deferent duct, ureter
urinary bladder
deferent duct
anteriorly crossing the ureter
seminal vesicle
secretes fructose, vit.C, amino acids, PGs
prostate gland

14. Inguinal herniation deep inguinal ring superficial inguinal ring
More common in males.
Starts above the inguinal ligament
Indirect inguinal herniation:
Starts at the deep inguinal ring, positioned in between the components of the spermatic cord, travels through the inguinal canal and can reach as far as the testis (testicular herniation).
Direct inguinal herniation:
Starts more medially, at the superficial inguinal ring. Not within, but next to the spermatic cord, usually do not reach the testis

15. Testis
Mediastinum testis
Testis
Covered partially by mesothel: tunica vaginalis testis (peritoneum).
Dense connective tissue capsule: tunica albuginea.
Capsule intrudes the testis at posterio-superior surface: mediastinum testis.
Connective tissue septa separating the lobules.
Lobules contain parenchyma (seminifrous tubules) and interstitium.

16. Testis: lobules Parenchyma:
Convoluted seminiferous tubules: spermatogenesis
spermatocytogenesys
Covered by a single layer of columnar cells (Sertoli cells)
nursing developing sperm.
Straight seminiferous tubules (tubuli recti): drain sperm into rete testis.
Contains only Sertoli cells, no spermatogenesis.
Relatively short, difficult to observe.
Interstitium:
Leydig cells: produce testosterone

17. Meiosis 2n
2n-2x2n
2x1n 1n

18. Spermatogenesis 1
Nested by Sertoli cells in convoluted seminiferous tubules, separated from toxins and the immune system (blood-testis barrier). Peripheral-central dislocation during development. Spiral spermatogenetic „waves” with 6 stages. Total development lasts about days.
Spermatogonium: stem cell
replicates itself (A-type) or differentiates (B-type)
B-type of spermatogonia divide by mitosis and the daughter cells, called
(1) primary spermatocytes enter the meiosis.
Prophase of first meiotic division last for 22 days in humans: well visible form!
(chromosomes, crossing over, 2x2n)
(2) Secondary spermatocyte (prespermatid): short lived, divide immediately, 2x1n
(4) Spermatid: small, round, haploid (1n), enters spermatocytogenesis

19. Tight junctions (zonula occludens)
Spermatogenesis 2
Spermiocytogenesis
Spermatid
Primary spermatocyte
Sertoli cell
Tight junctions (zonula occludens)
Blood-testis barrier
Spermatogonia
Myoid cell
Leydig cells

20. Spermiocytogenesis

21. Mature sperm

22. Convoluted seminiferous tubules

23. Primary spermatocytes
Spermatids
Spermatogonia
Sertoli cell

25. Interstitium: Leydig cells

26. Leydig cells
Myoid cells

27. Hormonal regulation

28. Rete testis in mediastinum
Tubuli testis
Rete testis
Network of tubules in dense connective tissue lined by cuboidal epithelia.

29. Epididymis Two types of duct:
Efferent ductules (10-20) in head arise from mediastinum of the testis. Highly curved tubules that transport sperm, reabsorb testicular fluid and remove the remaining residual bodies. Variable epithelial cells: high columnar cells with cilia mixed with low cuboideal cells without cilia; resulting in star-shaped lumen. Ductules are surrounded by a few layers of smooth muscle.
Ductus epididymidis in head, body and tail, will continue as deferent duct. Highly muscular, curly tubes. Store sperms, and the peristaltic movement of the muscular wall will release them during ejaculation. Also secretes several biologically active substances. Lined by high, regular, pseudostratified columnar epithelium with stereocilia.

30. Efferent ductules

31. Ductus epididymidis

32. Spermatic cord
Approximately 1cm thick structure in the inguinal canal to the testis.
Contains all the structures that supply the testis and epididymis:
Deferent duct
Deferential artery
Testicular artery and vein (pampiniform plexus)
Sympathetic and parasympathetic nerves
Genital branch of genitofemoral nerve (to cremaster m.)
Ilioinguinal nerve (ext surface, to spf. layers of scrotum
Surrounded by the same layers as the testis!

33. Deferent duct: Epithelium: pseudostratified columnar
Tunica propria mucosae
Muscularis: 3 layers of smooth muscles (2 spiral and a middle circular)