[Somatostatin inhibited pain modulation action of substance P in spinal cord]

In the present study, the effect of somatostatin (SST) on pain modulation induced by substance P in spinal cord was studied. The results showed that intrthecal injection of SST increases pain threshold, prevented pain response and c-fos expression in spinal cord induced by SP. Injection of formalin in the hindpaw induced pain response and increased the SP-LI, which could be inhibited by injection of SST. It is suggested that the analgesic effect of SST may be resulted from the inhibition of the noxious response induced by SP.