Ascending pain pathway is inhibited in dorsal midbrain by
The cell bodies of serotonin containing neurons are localized in the raphe nuclei of midbrain and brainstem. ... Serotonin therefore acts descending pathway to modulate spinal pain signals Ref: guyton and hall textbook of medical physiology 12 edition page number:699,700,701
5-HT (serotonin)
Noradrenaline 1
Substance P
Glutamate
Nervous system