Granulosa cells

Definition

Granulosa cells are somatic cells found in the ovarian follicles that surround and support developing oocytes. They play a crucial role in the regulation of reproductive hormones, particularly estrogen, and are essential for the maturation of oocytes during the menstrual cycle.

5 Must Know Facts For Your Next Test

1. Granulosa cells are responsible for the production of estrogen through the aromatization of androgens, which is crucial for regulating the menstrual cycle and maintaining reproductive health.
2. These cells proliferate in response to follicle-stimulating hormone (FSH), which enhances their ability to support oocyte development and hormone production.
3. Granulosa cells also secrete inhibin, a hormone that provides negative feedback to the pituitary gland to regulate FSH levels during the menstrual cycle.
4. During follicular atresia, granulosa cells undergo apoptosis, leading to the degeneration of non-dominant follicles in the ovary.
5. Granulosa cells are involved in creating a microenvironment around the oocyte that is essential for its growth, maturation, and eventual release during ovulation.

Review Questions

• How do granulosa cells interact with other ovarian cell types to support oocyte development?
  • Granulosa cells work closely with theca cells to support oocyte development. Theca cells produce androgens, which granulosa cells convert into estrogen through aromatase activity. This interaction is essential because estrogen not only aids in follicle maturation but also promotes further development of granulosa cells themselves. Additionally, both cell types respond to hormones like FSH, enhancing their collaborative role in the maturation process of the oocyte.
• Discuss the role of granulosa cells in hormonal regulation during the menstrual cycle.
  • Granulosa cells play a key role in hormonal regulation during the menstrual cycle by producing estrogen, which is vital for follicle development and ovulation. In response to FSH from the pituitary gland, granulosa cells proliferate and increase estrogen production. This surge in estrogen levels stimulates positive feedback on LH secretion, leading to ovulation. Furthermore, granulosa cells also secrete inhibin, which provides negative feedback to reduce FSH levels after ovulation, thus helping regulate the cycle effectively.
• Evaluate how dysfunction in granulosa cell function could impact female fertility.
  • Dysfunction in granulosa cell function can significantly impact female fertility by disrupting normal ovarian function. If granulosa cells fail to proliferate or produce adequate estrogen due to hormonal imbalances or other factors, it can lead to impaired oocyte maturation and reduced follicle viability. This dysfunction may result in conditions such as polycystic ovary syndrome (PCOS), where abnormal follicle development occurs. Such issues can ultimately hinder ovulation and reduce chances of conception, highlighting the critical role granulosa cells play in female reproductive health.

Related terms

Theca cells: Theca cells are steroidogenic cells that form a layer around the granulosa cells in ovarian follicles and are responsible for producing androgens that granulosa cells convert to estrogen.

Follicle-stimulating hormone (FSH): FSH is a hormone produced by the anterior pituitary gland that stimulates the growth and maturation of ovarian follicles and promotes the function of granulosa cells.

Oocyte: An oocyte is an immature egg cell found in the ovaries, which develops into a mature egg during the process of folliculogenesis, supported by granulosa cells.