New pharmacological strategies for pain relief.

The recent advances made in elucidating the processes of nociception have altered the way that chronic pain therapy and analgesic drug development are approached. Recent studies have highlighted new targets for drug discovery, including inhibition of inflammatory mediators (kinins, growth factors), newly expressed proteins (B1 receptors, COX-2), and blockers of afferent fiber activity (capsaicin analogues, ion channel blockers). In the CNS, a further multiplicity of strategies can be pursued, including the development of antagonists of specific neuropeptide and glutamate receptors or agonists for purine and amine receptors. Such drugs will inevitably supplement or replace conventional NSAID and opioid analgesics. Further characterization of gene regulation will allow the development of drugs that genetically modify cellular activity altered by chronic pain conditions.