Extrasegmental analgesia of heterotopic electroacupuncture stimulation on visceral pain rats

►Heterotopic EA stimulation trigger the pain-inhibiting effect of diffuse noxious inhibitory controls (DNIC). ►The PTN-NTS secondary neural pathway is involved in the EA analgesia. ►Small-diameter (Aδ and/or C) fibers are crucial for the extrasegmental analgesia.