Ascending pain pathway is inhibited in dorsal midbrain by encephalin anda) 5-HT (serotonin)b) Noradrenalinec) Substance Pd) Glutamatee) Adenosine: (A) ac, (B) a, (C) ab, (D) bc
Answer is C. Opioid interneurons inhibit the spinothalamic pain transmission after activation by serotonin and noradrenaline.