Menstrual Cycle and Hormonal Regulation

Puberty and Hormonal Triggers

• Critical Fat Mass: Puberty begins when an individual reaches a critical fat mass.
• Leptin Production: Adipose tissue produces the hormone leptin.
  • Leptin's Role: Travels in the circulation to the brain.

Hypothalamus and Kisspeptin

• Kisspeptin Production: Stimulated by leptin in the hypothalamus.
• Kisspeptin Interaction: Interacts with receptor GPR54 on neurons within the hypothalamus.

Gonadotropin-Releasing Hormone (GnRH)

• Production: Stimulated by kisspeptin interaction.
• Pulse Production:
  • Fast Pulses: Stimulate production of luteinizing hormone (LH) in the anterior pituitary.
  • Slow Pulses: Stimulate production of follicle-stimulating hormone (FSH) in the anterior pituitary.

Anterior Pituitary and Gonadotropins

• LH and FSH: Produced in response to GnRH pulses.
• Function: Travel to the female gonad (ovary) and are involved in:
  • Development of the female gamete during folliculogenesis.
  • Production of sex steroids.

Folliculogenesis

• Role of Hormones: LH and FSH crucial for follicle development.
• Endometrial Function: Sex steroids not only aid follicle development but are essential for endometrial function.

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The lecture aims to delve deeper into the process of folliculogenesis in subsequent sections.