Noxious – and potentially painful – stimuli are processed first in the dorsal horn of the spinal cord, making this region a possible target for pain therapeutics. But the organization of the dorsal horn and the precise roles of its neuronal populations are incompletely understood.
![man with back pain](http://news.vumc.org/wp-content/uploads/back-pain_iStock.jpg)
Laurie Lemons, Ph.D., and Ronald Wiley, M.D., Ph.D., investigated the role of dorsal horn neurons that respond to the signaling molecule neuropeptide Y (NPY). The researchers used a targeted toxin to selectively destroy neurons expressing the NPY receptor Y1R in rats. Then, they tested the rats’ behavioral responses – designed to require cerebral processing – to thermal and chemical pain stimuli.
They found that the loss of Y1R-expressing neurons reduced sensitivity to thermal stimuli and eliminated allodynia (pain from a non-painful stimulus – a common clinical pain-related problem), without interfering with the analgesic effects of morphine. The findings, reported in the Aug. 2 issue of Neuroscience, suggest that the spinal NPY system is an appropriate target for the development of new analgesic drugs.
This research was supported by the Department of Veterans Affairs.