Jul 31 2009
Researchers in Sweden are breaking boundaries in the field of nerve cell communication by creating the first artificial nerve cell capable of communicating with human nerve cells. The research will fuel understanding in the pathophysiology, molecular targets and therapies for the treatment of various nervous system disorders such as Parkinson's disease. The findings have been published in the journal Nature Materials.
Scientists have been stimulating nerve signals in the nervous system by using methods that are based on electrical stimulation. Cochlear implants, for example, are surgically inserted into the cochlea which is located in the inner ear, and electrodes are used in the brain directly. But the researchers from the Karolinska Institute and Linköping University in Sweden found that the current method activates all cell types in the area of the electrode; the result is lacklustre at best.
'Direct electrical interfacing suffers from some inherent problems, such as the inability to discriminate amongst cell types,' the study showed. 'There is a need for novel devices to specifically interface nerve cells.'
In this latest study, the researchers created a new type of 'delivery electrode' by using an electrically conducting plastic. This delivery electrode releases the neurotransmitters that brain cells use to communicate naturally.
'We demonstrate an organic electronic device capable of precisely delivering neurotransmitters in vitro and in vivo. In converting electronic addressing into delivery of neurotransmitters, the device mimics the nerve synapse,' the authors wrote.
The team also showed that the delivery electrode can be used to control the hearing function in the brains of guinea pigs.
'The 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,' explained chief researcher Professor Agneta Richter-Dahlfors of the Department of Physiology and Pharmacology at Karolinska Institutet in Sweden.
According to the researchers, 'delivery is achieved with minimal physiological disturbances, as electronic signals are translated into ion transport in the absence of fluid flow'.
Next on their list is the development of a small unit that can be implanted in the body. For Professor Richter-Dahlfors and her colleague Professor Barbara Canlon, this unit can be programmed to allow the flexible (i.e. as often or as seldom as needed) release of neurotransmitters for each patient.
The innovative technology will benefit patients suffering from various disorders including epilepsy and hearing loss.
'Having demonstrated the ability to translate electronic addressing signals, through neurotransmitter signalling, into brainstem responses, this technology establishes a new paradigm in machine-to-brain interfacing,' the authors wrote. 'These developments represent a significant step forward in biology-technology interfacing, and promise to pioneer further symbiosis of electronics and living systems.'
Source: Cordis