Neurotransmitters and neuropeptides in headache

For many decades, headache and migraine were thought to evolve from dilated cranial blood vessels. Vasoconstrictors such as ergotamine and, more recently, sumatriptan were considered appropiate treatments. With the introduction of animal models and the emergence of molecular pharmacology, this traditional concept has been challenged, and an important role for neuropeptides, neuronal receptors and neurogenic inflammation is emerging. Neurogenic inflammation develops within the meninges as a consequence of neuropeptide release from primary afferent fibers and has been hypothesized to be of importance in migraine. Neurogenic inflammation provides protection for many organs, contributes to tissue repair and serves as a useful model to define the receptor population and peptide mechanisms of relevance to drug discovery in migraine. The possible role played by neurotransmitters and neuropeptides in migraine and their receptors as potential targets for treatment will be discussed.