[Effect of oxytocin and cholecystokinin octapeptide (CCK-8) on electroacupuncture (EA) analgesia].

The effect of oxytocin (OT) and cholecystokinin octapeptide (CCK-8) on EA analgesia was studied in rats. The increase of 20.8-39.8% and 9.0-45.0% in pain threshold was observed respectively when ICV of CCK-8 or naloxone was combined with EA, these increases were lower than that in saline-EA group significantly, while the simultaneous ICV of OT and CCK-8 or OT and naloxone in combination with EA produced the increase of 76.2-116.6% and 41.8-104.5% in pain threshold separately. These results showed that only a small part in the role of OT enhancing EA analgesia was blocked by CCK-8 and naloxone. The data suggest that the role of OT in EA was not entirely dependent upon the endogenous opiate peptides.