Forum for Science, Industry and Business

Sponsored by:     3M 
Search our Site:

 

Studies Discover New Estrogen Activity in the Brain

01.08.2011
Research by University of Massachusetts Amherst neuroscientist Luke Remage-Healey and colleagues has for the first time provided direct evidence that estrogens are produced in the brain’s nerve cell terminals on demand, very quickly and precisely where needed. “This is an incredibly precise control mechanism and it solidifies a new role for estrogens in the brain,” says Remage-Healey.

Estrogens like estradiol are crucial in modulating neural circuits that govern such behaviors as feeding and reproduction, memory, cognition and neuroplasticity in animals and humans.

In a series of experiments with zebra finches, Remage-Healey and neuroendocrinologists from the University of California Los Angeles (UCLA) provide a new picture of neuron-produced estradiol suggesting that it acts remarkably like a classic neurotransmitter controlled by electrochemical events, in addition to its role as a hormone in the bloodstream, he adds.

“The fact that the brain synthesizes estradiol at the synapse in a very rapid, targeted way makes it almost a different beast than the estradiol we knew before. So we now know the brain can produce its own supply of estrogens that are not really acting like hormones anymore, but more like neurotransmitters. It’s the exact same molecule in birds, fish, dogs and humans. It’s the same molecule as is produced in the human ovary. But now we know that neurons can control the release of estrogens onto other neurons, in a way similar to the way neurotransmitters are controlled.”

These new findings also support the idea that neuroestrogens modulate information flow in the brain’s cortex in seconds to minutes, in contrast to the hours and days it takes for hormones circulating in the blood stream to have an effect. This work supported by the National Institutes of Health is described in a July issue of the Journal of Neuroscience.

“It’s clear now that neurons are producing estrogens in presynaptic terminals, the hand-shake zone where a signal between neurons is transmitted,” says Remage-Healey. He adds that these findings are extremely exciting because “presynaptic terminals are the interface between neurons. When that connection is strengthened in the presence of estradiol, it could lead to enhanced learning and plasticity.”

For these experiments, the UMass Amherst and UCLA researchers developed a microdialysis probe to conduct in vivo real-time testing in the forebrains of active, alert zebra finches. These robust little birds are awake and flying, singing, eating and drinking with a tiny micron-diameter probe implanted in their forebrains. The probe not only allows researchers to measure estradiol levels but to alter local potassium and calcium levels, chemicals that activate or inhibit neural activity.

In a clever twist, Remage-Healey and colleagues also use conotoxin, a very specific toxin produced by the cone snail. It targets only presynaptic nerve terminals that use a voltage-gated calcium channel. The researchers pump minute amounts of the toxin through the probe to precisely inhibit calcium channels in individual nerve terminals. In this way, they established that estradiol is calcium-dependent, is synthesized very rapidly in response to stimuli in the presynaptic terminal, but not in the neuronal cell body.

In a typical experiment, Remage-Healey and colleagues infuse artificial cerebrospinal fluid through the probe continuously over a 30-minute period. They receive back dialysate, from which they measure local estradiol concentration. Results challenge the traditional view that the brain is responding to estrogens produced elsewhere.

The UMass Amherst neuroestrogen expert adds, “In other experiments using this new technology we’ve shown that estradiol is changing in this same brain area when the animal hears a sound. This shows that estradiol is fluctuating much faster and in a more specific way than we understood before. Estrogens could therefore target their actions to certain neurons, synapse by synapse.”

Overall, the new findings could open the path to investigate more precisely the role of estrogens in learning, and perhaps reveal a way to deliver estradiol directly to neurons to enhance cognitive abilities without systemic side effects such as increased heart disease risk.

Luke Remage-Healey
413/545-0772
healey@cns.umass.edu

Luke Remage-Healey | Newswise Science News
Further information:
http://www.umass.edu

Further reports about: Amherst Brain Estrogen UCLA UMass activity calcium channel calcium level studies zebra finch

More articles from Life Sciences:

nachricht Single-stranded DNA and RNA origami go live
15.12.2017 | Wyss Institute for Biologically Inspired Engineering at Harvard

nachricht New antbird species discovered in Peru by LSU ornithologists
15.12.2017 | Louisiana State University

All articles from Life Sciences >>>

The most recent press releases about innovation >>>

Die letzten 5 Focus-News des innovations-reports im Überblick:

Im Focus: First-of-its-kind chemical oscillator offers new level of molecular control

DNA molecules that follow specific instructions could offer more precise molecular control of synthetic chemical systems, a discovery that opens the door for engineers to create molecular machines with new and complex behaviors.

Researchers have created chemical amplifiers and a chemical oscillator using a systematic method that has the potential to embed sophisticated circuit...

Im Focus: Long-lived storage of a photonic qubit for worldwide teleportation

MPQ scientists achieve long storage times for photonic quantum bits which break the lower bound for direct teleportation in a global quantum network.

Concerning the development of quantum memories for the realization of global quantum networks, scientists of the Quantum Dynamics Division led by Professor...

Im Focus: Electromagnetic water cloak eliminates drag and wake

Detailed calculations show water cloaks are feasible with today's technology

Researchers have developed a water cloaking concept based on electromagnetic forces that could eliminate an object's wake, greatly reducing its drag while...

Im Focus: Scientists channel graphene to understand filtration and ion transport into cells

Tiny pores at a cell's entryway act as miniature bouncers, letting in some electrically charged atoms--ions--but blocking others. Operating as exquisitely sensitive filters, these "ion channels" play a critical role in biological functions such as muscle contraction and the firing of brain cells.

To rapidly transport the right ions through the cell membrane, the tiny channels rely on a complex interplay between the ions and surrounding molecules,...

Im Focus: Towards data storage at the single molecule level

The miniaturization of the current technology of storage media is hindered by fundamental limits of quantum mechanics. A new approach consists in using so-called spin-crossover molecules as the smallest possible storage unit. Similar to normal hard drives, these special molecules can save information via their magnetic state. A research team from Kiel University has now managed to successfully place a new class of spin-crossover molecules onto a surface and to improve the molecule’s storage capacity. The storage density of conventional hard drives could therefore theoretically be increased by more than one hundred fold. The study has been published in the scientific journal Nano Letters.

Over the past few years, the building blocks of storage media have gotten ever smaller. But further miniaturization of the current technology is hindered by...

All Focus news of the innovation-report >>>

Anzeige

Anzeige

Event News

See, understand and experience the work of the future

11.12.2017 | Event News

Innovative strategies to tackle parasitic worms

08.12.2017 | Event News

AKL’18: The opportunities and challenges of digitalization in the laser industry

07.12.2017 | Event News

 
Latest News

Engineers program tiny robots to move, think like insects

15.12.2017 | Power and Electrical Engineering

One in 5 materials chemistry papers may be wrong, study suggests

15.12.2017 | Materials Sciences

New antbird species discovered in Peru by LSU ornithologists

15.12.2017 | Life Sciences

VideoLinks
B2B-VideoLinks
More VideoLinks >>>