Grant: Operating Grant

Chronic pain has a major effect on the quality of life of patients with MS. "Neuropathic" pain, which arises when there is an injury or disease in the nervous system, is the most prevalent and difficult to treat pain syndrome seen in MS patients. Unfortunately, there are few effective treatments to relieve neuropathic pain in MS because currently very little is known about its underlying causes. Within the central nervous system (CNS), cells communicate via the release of neurotransmitters. The amino acids glutamate and gamma-aminobutyric acid (GABA) are the two major neurotransmitters required for excitatory and inhibitory signals respectively. Serotonin and noradrenaline, biogenic amines, are also important for communication within the CNS, often suppressing signals between cells. In diseases such as MS, the balance between these different 'excitatory' and 'inhibitory' neurotransmitters can be disturbed. Our research will test the hypothesis that in a mouse model of MS, alterations in the levels of these excitatory and inhibitory neurotransmitters is the major underlying cause of neuropathic pain and disability that arises in the disease. Using an animal model of MS, we will test how specific drugs, known to significantly alter the levels of these different neurotransmitters, affect pain sensitivity and symptom severity. Because the different drugs that we will be testing affect only certain neurotransmitters systems, we will be able to isolate and identify which of the different affected neurotransmitters is most important for causing pain and disability in the disease. By identifying these underlying causes, we will be in a strong position to develop new treatments for patients with MS that will help to restore function and relieve the pain and discomfort associated with the disease.