Cortical Regulation of Striatal Dopamine Neurons: Implications for the Neuropathology of Tourette Syndrome

Grant Type
Basic
Grant Year
1993
Institution Location
PA
Institution Organization Name
University of Pittsburgh
Investigators Name
Finlay, Janet, PhD

Tourette Syndrome is a neurological disorder characterized by chronic involuntary motor tics and verbalizations. Unfortunately, the disruption in brain function that is responsible for Tourette Syndrome continues to elude researchers. However, there is evidence that the neurotransmitter dopamine (which functions to relay messages between cells in the brain) may be involved in the underlying abnormality in brain function associated with the disorder. This neurotransmitter is contained in groups of neurons that transmit information to discrete regions of the brain including the cortex as well as underlying areas such as the striatum. The cortex and striatum interact with one another in a very complex, and as yet not entirely understood, manner. We propose that a decrease in the function of the dopamine containing neurons in the cortex leads to an increase in the activity of the dopamine neurons in striatum and this, in turn, gives rise to the symptoms associated with TS. Thus, drugs used in treating TS may reduce the symptoms of the disorder by counteracting the heightened activity of the dopamine neurons in striatum. The proposed research is aimed at understanding the interaction between dopamine neurons in the cortex and those in the striatum. Specifically, we will examine whether increases or decreases in the amount of dopamine in the cortex alter the synthesis of dopamine in the striatum. This work will be accomplished, in part, using a relatively new technique called in vivo microdialysis which allows researchers to monitor the synthesis of dopamine in discrete regions of the brain in behaving animals. With the information gained from these experiments, we will begin to understand how a disruption in the interaction between the dopamine-rich brain regions may result in the involuntary motor tics and verbalizations associated with Tourette Syndrome. This information will be critical in developing more effective treatments. Janet M. Finlay, Ph.D. University of Pittsburgh, Pittsburgh, PA Award $25,000 Tourette Association of America Inc. – Research Grant Award 1993