July 08, 2009 --
Scientists at the Swedish medical university Karolinska Institutet and
Linköping University are well on the way to creating the first
artificial nerve cell that can communicate specifically with nerve
cells in the body using neurotransmitters. The technology has been
published in an article in Nature Materials.
methods that are currently used to stimulate nerve signals in the
nervous system are based on electrical stimulation. Examples of this
are cochlear implants, which are surgically inserted into the cochlea
in the inner ear, and electrodes that are used directly in the brain.
One problem with this method is that all cell types in the vicinity of
the electrode are activated, which gives undesired effects.
Scientists have now used an electrically conducting plastic to create a
new type of "delivery electrode" that instead releases the
neurotransmitters that brain cells use to communicate naturally. The
advantage of this is that only neighbouring cells that have receptors
for the specific neurotransmitter, and that are thus sensitive to this
substance, will be activated.
The scientists demonstrate in the
article in Nature Materials that the delivery electrode can be used to
control the hearing function in the brains of guinea pigs.
ability to deliver exact doses of neurotransmitters opens completely
new possibilities for correcting the signalling systems that are faulty
in a number of neurological disease conditions", says Professor Agneta
Richter-Dahlfors who has led the work, together with Professor Barbara
The scientists intend to continue with the development
of a small unit that can be implanted into the body. It will be
possible to program the unit such that the release of neurotransmitters
takes place as often or as seldom as required in order to treat the
individual patient. Research projects that are already under way are
targeted towards hearing, epilepsy and Parkinson's disease.
Source : Karolinska Institutet