molecular effects

Last reviewed 01/2018

Oestrogens are similar to all steroids in that they bind to intracellular receptors. The oestrogen-receptor complex then interacts with both DNA and chromatin to transcribe specific mRNA. The mRNA is then translated into specific proteins.

Oestrogen receptors are concentrated within tissue that they have significant physiological effects upon e.g. uterus, vagina, anterior pituitary gland. Each cell has around 10-20,000 receptors. Binding of oestrogen causes dimerization of the receptor. Once RNA synthesis has occurred, new receptors need to be synthesized.

The number of oestrogen receptors may be modulated by other hormones:

• progesterone - decreases receptor concentration
• prolactin - increases numbers