Neuroscientists at the University of Massachusetts, Amherst (UMass), and the University of California, Los Angeles, have found that estrogen can act as a neurotransmitter, in addition to its usual role as a hormone in the bloodstream, according to a study published in the Journal of Neuroscience last month.
Estradiol—the type of estrogen that is most prevalent in the body during a female’s reproductive years—is produced by the ovaries and then enters the blood stream where it takes hours or days to bring about changes in the cortex region of the brain. But in of zebra finches, neurons also produced estradiol directly inside the presynaptic terminal. Within a matter of seconds, the hormone then crossed the synapses of the auditory forebrain—the area of the brain that responds to sound.
This is “similar to the way neurotransmitters are controlled,” Luke Remage-Healey, neuroscientist at UMass, said in a press release.
This is the first time that scientists have directly measured estrogen levels over a short period of time in the brain of a live animal to determine how estradiol is produced and transmitted between neurons. Because of the brain’s ability to produce it quickly and in a precise location, Remage-Healey and his colleagues believe that estradiol, which is known to play a role in memory, cognition, and neuroplasticity, may someday be a target to improve brain function.