[Effect of brain somatostatin on electroacupuncture analgesia of rat]

The purpose of this study was to verify the role of somatostatin (Som) of brain in analgesia of electroacupuncture (EA). Intracerebroventricular (icv) injection of Som caused a more marked elevation of pain threshold and of EA analgesic effect, but the activity of Ca(2+)-APTase in hippocampus was significantly decreased; The Som and GABA levels in hippocampus and brain stem were decreased by EA analgesia. The Som in hippocampus and brain stem were obviously depleted by icv injection of cycteamine, but without any change of pain threshold and analgesic effect of EA. These results indicated that the exogenous Som of brain potentiated the analgesic effect of EA, however, the decrease of endogenous of some brain regions took part in the process of EA analgesia.