The male reproductive system consists of both internal and external structures that work together to produce sperm. The testes contain seminiferous tubules where spermatogenesis, the process of sperm production, occurs through the interactions of Sertoli and Leydig cells. Sertoli cells provide physical and nutritional support to germ cells and help maintain the blood-testis barrier. Leydig cells in the testes produce androgens like testosterone. Other structures like the epididymis, vas deferens, seminal vesicles and prostate gland help store and transport sperm and seminal fluid. Factors like temperature, season, and hormones regulate spermatogenesis.

1. Male Reproductive System
Dr.Nabeel Beeran MBBS, MD
Department of Physiology
09/08/2019
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2. Specific Learning Objectives
At the end of the class you should be able to:
• Name and give the functions of different parts of
male reproductive system.
• List the functions of sertoli and leydig cells.
• Understand the importance of blood testis barrier
• Describe the steps and mechanism of
spermatogenesis
• Describe the factors affecting spermatogenesis
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4. Testes:
Ducts:
• Epididymis
• Vas deferens
• Ejaculatory ducts
• Urethra
Accessory sex glands:
• Seminal vesicle
• Prostate gland
• Bulbourethral glands
Supporting structures:
• Spermatic cord
• Scrotum
• Penis 4

5. Testes
Interstitial compartment
• Leydig cells
• Blood vessels
• Lymphatics
Seminiferous tubular compartment
• Supporting cells/ Sertoli cells
• Germ cells/spermatogenic cells
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6. Sertoli cells:
• Basal compartment
• Adluminal compartment
Blood-testis barrier:
Significance:
• Protects the germ cells
• Prevents entry of germ
cells in to circulation.
• Maintains composition of
fluid
• Maintains higher
osmolality
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7. Functions of sertoli cells:
• Physical support & nutrition
• Phagocytic function
• Blood-testis barrier:
• Secretory function
- MIS
- Androgen binding protein(ABP)
- H-Y antigen
- Inhibin, Activin
- Estrogen
- Transport proteins: transferrin and ceruloplasmin
- Plasminogen activator – support spermiation
- Seminiferous tubular fluid:
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8. Functions of testes?
• Spermatogenesis
• Endocrine function
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9. Spermatogenesis
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10. • Spermatogenesis refers to the process of
formation of spermatozoa from the primitive
germ cells (spermatogonia).
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11. Spermatogenesis
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12. Spermatogenesis
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Spermiogenesis
Spermiation

14. Factors affecting spermatogenesis:
• Temperature
• Seasonal variation
• Infectious disease
• Hormonal regulation of spermatogenesis
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16. Semen Analysis
• Volume: 2- 5 ml
• Milky apperance
• Alkaline pH: 7.5
• Specific gravity: 1.028
• Composition:
- Spermatozoa
- Epididymal secretion
- Secretions of seminal vesicles: fructose, fibrinogen,
prostaglandins, flavins, vit C.
- Secretion of prostate gland: spermine, citric acid,
cholesterol, clotting enzymes, fibrinolysin, zinc, acid
phosphatase, Prostate specific antigen (PSA)
- Secretion of bulbourethral gland: mucoid consistency
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17. Endocrine Functions of Testes
• Leydig cells of testes produce male sex
hormones known as androgens.
• Sertoli cells of testes secrete oestrogen,
inhibin and activin.
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18. Summary
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19. References
• Guyton and Hall Textbook of Medical Physiology ,
• GK Pal Comprehensive textbook of Medical
Physiology. Volume 1
• Textbook of Medical Physiology (2nd edition)- Indu
Khurana
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20. Thank
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