title: The opiate antagonist naloxone does not consistently block inhibition of spinal nociceptive transmission produced by stimulation in lateral midbrain reticular formation of the cat.
abstract: Electrical stimulation in the lateral midbrain reticular formation (LRF) inhibited the responses of spinal dorsal horn neurons to noxious (50 degrees C) skin heating. Systemic administration of naloxone (0.1-2 mg/kg) had no effect on inhibition produced by LRF stimulation in 10 units, while this inhibition was partially blocked in 3 units. The results indicate that endogenous opiates are not primarily involved in mediating descending inhibition from LRF stimulation.
mesh_terms: D000344:Afferent Pathways / Q000503:physiopathology; D000818:Animals; D002415:Cats; D004723:Endorphins / Q000502:physiology*; D008636:Mesencephalon / Q000503:physiopathology*; D009270:Naloxone; D010146:Pain / Q000503:physiopathology*; D010646:Phentolamine; D011433:Propranolol; D012154:Reticular Formation / Q000503:physiopathology*; D013116:Spinal Cord / Q000503:physiopathology
chemical_list: D004723:Endorphins; D009270:Naloxone; D011433:Propranolol; D010646:Phentolamine