Forum for Science, Industry and Business

Sponsored by:     3M 
Search our Site:

 

Vollum scientists find new form of dopamine transmission

15.07.2004


An Oregon Health & Science University research team has uncovered a novel form of transmission between neurons in the brain that is mediated by dopamine. The neurons are found in parts of the brain associated with movement, substance abuse and mental disorders.
Scientists at the Vollum Institute, OHSU School of Medicine, reported in a study published in the journal Neuron that the neurotransmitter dopamine is released from midbrain nerve cells in a much more precise, targeted manner than previously thought. They discovered that dopamine molecules are released as packages from stores, or vesicles, in branch-like extensions of neurons called dendrites. The dopamine travels to dopamine receptors on tiny terminals within milliseconds. Until now, scientists had only detected the release of dopamine in the midbrain and suspected that the neurotransmitter was dispersed over wide areas to reach receptors.

"We’ve demonstrated that this synaptic current is over and done within a second," said John Williams, Ph.D., senior scientist at the Vollum Institute, OHSU School of Medicine, and a study co-author. "We knew dopamine was released in this place, we knew the cells were sensitive to dopamine, but nobody had been able to put the two together."


In addition, the study found that the current is highly sensitive to drugs such as cocaine, which increased the size and duration of the current, and even levodopa, or L-dopa, a drug converted in the brain to dopamine and which enhanced dopamine stores. L-dopa is used clinically to treat Parkinson’s disease symptoms.

The study focused on dopamine transmission in the substantia nigra, a part of the midbrain where dopamine cells lose function, leading to Parkinson’s disease, and the ventral tegmental area, a region containing dopamine cells involved in the rewarding properties of many abused drugs, such as cocaine, amphetamine, opioids and nicotine.

Researchers believe pinpointing alterations in the system under pathological conditions such as Parkinson’s disease, schizophrenia, attention deficit hyperactivity disorder and substance abuse could help them someday identify new therapeutic targets for these conditions.

"We don’t know yet what the real significance of this process is going to be down the road," said Michael Beckstead, Ph.D., postdoctoral fellow at the Vollum Institute and the study’s lead author. "For now, we’re looking at a basic physiological phenomenon."

Jonathan Modie | EurekAlert!
Further information:
http://www.ohsu.edu

More articles from Life Sciences:

nachricht One step closer to reality
20.04.2018 | Max-Planck-Institut für Entwicklungsbiologie

nachricht The dark side of cichlid fish: from cannibal to caregiver
20.04.2018 | Veterinärmedizinische Universität Wien

All articles from Life Sciences >>>

The most recent press releases about innovation >>>

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

Im Focus: Spider silk key to new bone-fixing composite

University of Connecticut researchers have created a biodegradable composite made of silk fibers that can be used to repair broken load-bearing bones without the complications sometimes presented by other materials.

Repairing major load-bearing bones such as those in the leg can be a long and uncomfortable process.

Im Focus: Writing and deleting magnets with lasers

Study published in the journal ACS Applied Materials & Interfaces is the outcome of an international effort that included teams from Dresden and Berlin in Germany, and the US.

Scientists at the Helmholtz-Zentrum Dresden-Rossendorf (HZDR) together with colleagues from the Helmholtz-Zentrum Berlin (HZB) and the University of Virginia...

Im Focus: Gamma-ray flashes from plasma filaments

Novel highly efficient and brilliant gamma-ray source: Based on model calculations, physicists of the Max PIanck Institute for Nuclear Physics in Heidelberg propose a novel method for an efficient high-brilliance gamma-ray source. A giant collimated gamma-ray pulse is generated from the interaction of a dense ultra-relativistic electron beam with a thin solid conductor. Energetic gamma-rays are copiously produced as the electron beam splits into filaments while propagating across the conductor. The resulting gamma-ray energy and flux enable novel experiments in nuclear and fundamental physics.

The typical wavelength of light interacting with an object of the microcosm scales with the size of this object. For atoms, this ranges from visible light to...

Im Focus: Basel researchers succeed in cultivating cartilage from stem cells

Stable joint cartilage can be produced from adult stem cells originating from bone marrow. This is made possible by inducing specific molecular processes occurring during embryonic cartilage formation, as researchers from the University and University Hospital of Basel report in the scientific journal PNAS.

Certain mesenchymal stem/stromal cells from the bone marrow of adults are considered extremely promising for skeletal tissue regeneration. These adult stem...

Im Focus: Like a wedge in a hinge

Researchers lay groundwork to tailor drugs for new targets in cancer therapy

In the fight against cancer, scientists are developing new drugs to hit tumor cells at so far unused weak points. Such a “sore spot” is the protein complex...

All Focus news of the innovation-report >>>

Anzeige

Anzeige

VideoLinks
Industry & Economy
Event News

Invitation to the upcoming "Current Topics in Bioinformatics: Big Data in Genomics and Medicine"

13.04.2018 | Event News

Unique scope of UV LED technologies and applications presented in Berlin: ICULTA-2018

12.04.2018 | Event News

IWOLIA: A conference bringing together German Industrie 4.0 and French Industrie du Futur

09.04.2018 | Event News

 
Latest News

Magnetic nano-imaging on a table top

20.04.2018 | Physics and Astronomy

Start of work for the world's largest electric truck

20.04.2018 | Interdisciplinary Research

Atoms may hum a tune from grand cosmic symphony

20.04.2018 | Physics and Astronomy

VideoLinks
Science & Research
Overview of more VideoLinks >>>