Application of Biosensors to the Measurement of Neurotransmitter function

Abstract

The 1990s is the “decade of the brain” and it has seen considerable advances in the methodology available for investigating brain function in relation to behavioral and physiological responses. The most obvious of such approaches is the use of imaging techniques (e.g., position emission tomography and functional nuclear magnetic resonance) to probe brain region structure and neurochemistry. An alternative approach is to develop biosensors that can be implanted into brain tissue to measure changes in extracellular levels of various neurochemicals including neurotransmitters, neuromodulators, products of receptor occupation (e.g., cyclic AMP), products of intracellular metabolism, products of oxidative stress, and drugs. The development of these in vivo probe techniques has resulted in new understanding of the action of drugs; one of the best examples is the establishment of a link between drug dependence and activation of dopamine mesolimbic function. Equally important are the new data becoming available on neurotransmitter control of behavior and the processes involved in neurodegeneration.