Forum for Science, Industry and Business

Sponsored by:     3M 
Search our Site:

 

UCSD Biologists Discover That Nerve Activity, Not Just Genetics Controls Kinds Of Neurotransmitters Produced

03.06.2004


Photo shows different neurotransmitters in red and purple in normal frog embryos and embryos with decreased and increased nerve activity (from top to bottom) Photo credit: Laura N. Borodinsky, UCSD


Neurobiologists at the University of California, San Diego have discovered that altering electrical activity in nerve cells can change the chemical messengers the cells generate to communicate with other cells, a finding that may one day lead to new treatments for mood and learning disorders.

In a study published in the June 3rd issue of the journal Nature, a team led by UCSD professor of biology Nicholas Spitzer shows that manipulating the electrical activity of developing nerve cells can alter the type of neurotransmitter—chemicals that carry information between nerve cells at junctions called “synapses”—they produce. A review paper discussing these results will appear in July in Trends in Neurosciences. The results are important because scientists had long believed that the different kinds of neurotransmitters used by different nerve cells were genetically programmed into the cell.

"If you were to ask neuroscientists what learning is in cellular and molecular terms, none would have said it is the changing identity of neurotransmitters,” says Spitzer. “That would have been heresy because everyone thought neurotransmitter identity was genetically programmed. Our results show that by altering neural activity, you can change the identity of the neurotransmitter a particular cell produces, raising the possibility that disorders caused by problems with neurotransmitters could be treated by modifying neural activity.”



In the study, the UCSD group increased or decreased the electrical activity in frog embryonic spinal nerve cells by altering the current through nerve cell membranes with drugs or by genetic manipulation. They found that increases in activity increased the levels of neurotransmitters that inhibit the activity of nerve cells across the synapse and decreased the levels of neurotransmitters that stimulate nerve cells. Decreasing electrical activity had the opposite effect.

These results led the researchers to propose that while genes control the formation of structures that produce electrical activity in nerve cells, the activity itself can determine what neurotransmitters are produced. According to Spitzer, this could provide flexibility for the growth and operation of the nervous system.

“Biology is a little sloppy,” explains Spitzer. “A nerve cell may need to grow to the other side of the developing brain and form a synapse there. Genes can do a lot to specify where to grow, but precision is not absolute. So instead of genes specifying everything, activity can play a role by fine tuning what neurotransmitters are expressed when the nerve cell finds its target.”

It is not yet clear how activity affects neurotransmitters in the adult nervous system, but Spitzer thinks there is a good chance activity will play a similar role there as well.

“Often the processes we see in the embryonic nervous system we also see in the adult, albeit in a much more muted way,” he says.

If so, these findings could open new avenues for treating mental illnesses like depression, phobias, schizophrenia and bipolar disorder, which together affect 20 percent of the U.S. population each year, with estimated cost of treatment and lost productivity totaling approximately $150 billion, according to the U.S. Surgeon General.

“Focal stimulation of the brain to elicit changes in neurotransmitter production could have advantages over current drug treatments and electroconvulsive therapy—stimulation of the whole brain with electric current,” notes Spitzer. “These treatments work for many patients, but both treat the entire brain in an imprecise way and have side effects.”

The first author on the paper, Laura Borodinsky, a postdoctoral fellow in Spitzer’s laboratory, is now studying how the cells across the synapse receiving the neurotransmitter change in response to being exposed to a different neurotransmitter. Using changes in activity to treat neural disorders would depend on the ability of these cells to respond appropriately to the new neurotransmitter. Further research is also needed, the UCSD scientists say, to determine if the 50 to 100 other known neurotransmitters are also regulated by activity.

Other UCSD contributors to the publication were Cory Root, Julia Cronin, Sharon Sann and Xiaonan Gu. The study was supported by the National Institutes of Health, National Science Foundation and Merck.


Media Contact: Sherry Seethaler (858) 534-4656
Comment: Nicholas Spitzer (858) 534-2456

Sherry Seethaler | UCSD
Further information:
http://ucsdnews.ucsd.edu/newsrel/science/sactivity.asp

More articles from Life Sciences:

nachricht Climate Impact Research in Hannover: Small Plants against Large Waves
17.08.2018 | Leibniz Universität Hannover

nachricht First transcription atlas of all wheat genes expands prospects for research and cultivation
17.08.2018 | Leibniz-Institut für Pflanzengenetik und Kulturpflanzenforschung

All articles from Life Sciences >>>

The most recent press releases about innovation >>>

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

Im Focus: Color effects from transparent 3D-printed nanostructures

New design tool automatically creates nanostructure 3D-print templates for user-given colors
Scientists present work at prestigious SIGGRAPH conference

Most of the objects we see are colored by pigments, but using pigments has disadvantages: such colors can fade, industrial pigments are often toxic, and...

Im Focus: Unraveling the nature of 'whistlers' from space in the lab

A new study sheds light on how ultralow frequency radio waves and plasmas interact

Scientists at the University of California, Los Angeles present new research on a curious cosmic phenomenon known as "whistlers" -- very low frequency packets...

Im Focus: New interactive machine learning tool makes car designs more aerodynamic

Scientists develop first tool to use machine learning methods to compute flow around interactively designable 3D objects. Tool will be presented at this year’s prestigious SIGGRAPH conference.

When engineers or designers want to test the aerodynamic properties of the newly designed shape of a car, airplane, or other object, they would normally model...

Im Focus: Robots as 'pump attendants': TU Graz develops robot-controlled rapid charging system for e-vehicles

Researchers from TU Graz and their industry partners have unveiled a world first: the prototype of a robot-controlled, high-speed combined charging system (CCS) for electric vehicles that enables series charging of cars in various parking positions.

Global demand for electric vehicles is forecast to rise sharply: by 2025, the number of new vehicle registrations is expected to reach 25 million per year....

Im Focus: The “TRiC” to folding actin

Proteins must be folded correctly to fulfill their molecular functions in cells. Molecular assistants called chaperones help proteins exploit their inbuilt folding potential and reach the correct three-dimensional structure. Researchers at the Max Planck Institute of Biochemistry (MPIB) have demonstrated that actin, the most abundant protein in higher developed cells, does not have the inbuilt potential to fold and instead requires special assistance to fold into its active state. The chaperone TRiC uses a previously undescribed mechanism to perform actin folding. The study was recently published in the journal Cell.

Actin is the most abundant protein in highly developed cells and has diverse functions in processes like cell stabilization, cell division and muscle...

All Focus news of the innovation-report >>>

Anzeige

Anzeige

VideoLinks
Industry & Economy
Event News

LaserForum 2018 deals with 3D production of components

17.08.2018 | Event News

Within reach of the Universe

08.08.2018 | Event News

A journey through the history of microscopy – new exhibition opens at the MDC

27.07.2018 | Event News

 
Latest News

Smallest transistor worldwide switches current with a single atom in solid electrolyte

17.08.2018 | Physics and Astronomy

Robots as Tools and Partners in Rehabilitation

17.08.2018 | Information Technology

Climate Impact Research in Hannover: Small Plants against Large Waves

17.08.2018 | Life Sciences

VideoLinks
Science & Research
Overview of more VideoLinks >>>