ANA Continuing Education | Menopause Health Educators Program: Monograph 3, page 2

Estrogen and the Brain

Estrogen has a significant effect on the brain, an effect that begins in utero. This is the case even for men, who convert testosterone into estrogen for use in the brain. Estrogen works through a number of mechanisms that alter neurotransmitter activity and protect the neurons of the brain from injury. Research, including in vitro studies, has revealed the following actions for estrogen:(1-7)

stimulates the expression of factors that promote neuronal growth within the central nervous system (CNS)
protects neurons from ß-amyloid toxicity (a feature of Alzheimer's disease)
stimulates the regeneration of axons and synapses
maintains viability and survival of neurons, thus preserving the information-processing capability and storage capacity of a brain cell
increases regional cerebral blood flow
stimulates production of the neurotransmitters acetylcholine and serotonin

The actions of estrogen on neurotransmitter systems are specific, that is to say, estrogen is not a general "tonic." Instead, estrogen can be directly linked with certain systems and their domains, or areas of influence (Table 1).

Table 1

previous: Introduction
next: Cognition