Novel molecular targets in pain control.
OBJECTIVE
The complexity of pain processing in clinical pain conditions and in animal models has revealed many time-related changes and an abundance of molecular drug targets. There continues to be insecurity, however, about new target validation in clinical pain and thus most analgesia development is of high risk for evolving new pain therapies. The present review highlights a number of molecular targets being pursued for pain control.


RESULTS
Many pain targets are critically dependent on the pain model/lesion type. Neural and glial plasticity, ranging from changes in molecular expression and receptor phosphorylation to profound morphological reorganization, has been described under these conditions. Pain modulation has been shown to involve all major families of regulatory proteins such as the G-protein coupled receptors, ion channels, regulatory enzymes, neurotrophins, and kinases, offering an abundance of targets and therapeutic opportunities for symptomatic pain relief.


CONCLUSIONS
Many molecular targets have been highlighted with some being the focus of current analgesia research. Some of these (e.g. vanilloid receptor 1, cannabinoid receptor 1, sodium channel NaV 1.8) have been evaluated in animal studies and in preliminary clinical studies, but others are highly novel and riskier analgesia pain targets (e.g. metabotropic glutamate receptors, sensory neurone specific receptors, kinase inhibitors).
Dray
Andy
A
AstraZeneca Research & Development Montreal, Canada. andy.dray@astrazeneca.com