Question

After lactation, the mammary gland regresses and returns to a resting state, which of the following occurs during regression

1.Apoptotic cell death and tissue remodelling
2.Increase in adipose tissue
3.Decrease in adipose tissue
4.Secretion is reabsorbed

• A. 1 only
• B. 2 only
• C. 2, 3 and 4 only
• D. 1, 3 and 4 only.

Answer 1

The correct option is D 1, 3 and 4 only.

The mammary gland is dynamically regulated by the reproductive state. During pregnancy, there is a massive increase in the number of luminal epithelial cells in the breast, which are destined to become the milk factories after birth.
Lactation describes the production of breast milk and its secretion from the mammary gland after delivery. But after the lactation period is over the mammary cells start involution.
Regression means returning of the mammary gland to its near to pre-pregnant state by eliminating unnecessary secretory epithelial cells by programmed cell death (apoptosis) and tissue remodelling programme.
After lactation, the mammary gland undergoes weaning-induced mammary gland involution. Mammary gland involution is a highly complex multi-step process in which the lactating gland returns to morphologically near to pre-pregnant state. This development stage is characterised by a high degree of epithelial cell death by apoptosis (the process of programmed cell death) and cell remodelling, decrease in adipose tissue. Secretion is also reabsorbed by the lactating mammary glands.