Lecture on Erectile Function and Physiology

Introduction

• Importance of erectile function from a reproductive standpoint.
• Common issue of erectile dysfunction.
• Understanding normal function is crucial to address dysfunctions.
• Utilization of cadavers to study anatomy and physiology of erections.

Overview of Erection

• Male erection: enlargement and stiffening of the penis.
• Female equivalent: clitoris (more similarities than often realized).

Stimulation for Erection

Psychological Stimulation

• Stimulation can be psychological from the brain:
  • Visual stimuli (e.g., attractiveness)
  • Auditory stimuli (e.g., hearing nice things)
  • Olfactory (smells)
  • Imagined scenarios

Tactile Stimulation

• Stimulation of genital organs and surrounding areas.
• Glans penis: most sensitive area, packed with sensory nerve endings.
• Signal travels via the pudendal nerve to spinal cord.

Nervous System Involvement

• Signals may not need to reach the brain for erection due to spinal cord reflexes.
• Reflexive activation within sacral portion of spinal cord is key.
• Parasympathetic nervous system is involved:
  • Part of autonomic nervous system.
  • Controls erectile tissue within the penis.

Role of Testosterone

• Primary male sex hormone.
• Affects bone health, muscle mass, fat distribution, red blood cell production.
• Influences libido and erectile function.
• Promotion of home testing kits for testosterone levels.

Anatomy of Erectile Tissues

Three Cylindrical Masses of Erectile Tissue

1. Corpus Spongiosum
   • Keeps urethra open for seminal fluid.
2. Corpora Cavernosa (two masses)
   • Contains cavernous erectile tissue with blood sinuses.
   • Deep arteries of the penis provide important blood supply.

Physiology of an Erection

• Psychological or tactile stimuli activate parasympathetic neurons in sacral spinal cord (S2, S3, S4).
• Neurons send signals to erectile tissue causing nitrous oxide release.
• Nitrous oxide:
  • Vasodilates deep arteries, increasing blood flow.
  • Relaxes smooth muscle, enlarging blood sinuses.
  • Compresses veins to maintain erection by limiting blood outflow.

Conclusion

• Erection is maintained until climax or cessation of stimulus.
• Lecture emphasized anatomical and physiological aspects of erections.

Additional Resources

• Check testosterone levels with Let's Get Checked.
• Engage with provided links for discounts and support.

Note: While the lecture included a promotional segment, it was integral to the discussion on testosterone's role in erectile function.