| abstract |
The present invention features methods and compositions for preventing, reducing, or treating a traumatic, metabolic or toxic peripheral nerve lesion or pain including, for example, neuropathic pain, inflammatory and nociceptive pain by administering to a mammal in need thereof a compound that reduces the expression or activity of BH4. According to this invention, this reduction may be achieved by reducing the enzyme activity of any of the BH4 synthetic enzymes, such as GTP cyclohydrolase (GTPCH), sepiapterin reductase (SPR), or dihydropteridine reductase (DHPR); by antagonizing the cofactor function of BH4 on BH4-dependent enzymes; or by blocking BH4 binding to membrane bound receptors. The compounds of the invention may be administered alone or in combination with a second therapeutic agent. The invention also provides methods for diagnosing pain or a peripheral nerve lesion in a mammal by measuring the levels of BH4 or its metabolites in biological sample. Alternatively, pain or a peripheral nerve lesion may be diagnosed by measuring the levels or activity of any one of the BH4 synthetic enzymes in tissue samples of a mammal. Also disclosed are screening methods that make use of BH4 or BH4 synthetic enzymes, BH4-dependent enzymes, and BH4-binding receptors for the identification of novel therapeutics for the treatment, prevention, or reduction of pain. |