[Effects of intraperitoneal injection of naloxone on the analgesic effect and the changes of brain catecholamine contents induced by electroacupuncture in rats].
Rats were randomly divided into 4 groups: Control, Electro-acupuncture (EA), Naloxone and Naloxone plus EA. The content of noradrenaline (NA) and dopamine (DA) in brain stem, diencephalon and telencephalon were determined by spectrofluorometry. It was found that the pain threshold increased and the NA content in the telencephalon decreased and the DA level in the brain stem increased markedly after EA. Naloxone injection partially decreased the analgesic effect of EA and abolished the EA-induced elevation of DA in the brain stem and attenuated the NA level in the diencephalon after EA. These results suggest that morphine receptor may play an important role in EA analgesia and this may be partially carried out through the brain catecholamine system.
Wang
Y J
YJ
Wang
S K
SK
D000818:Animals; D001921:Brain / Q000378:metabolism*; D002395:Catecholamines / Q000378:metabolism*; D004298:Dopamine / Q000378:metabolism; D015671:Electroacupuncture; D007274:Injections, Intraperitoneal; D008297:Male; D009270:Naloxone / Q000494:pharmacology*; D009638:Norepinephrine / Q000378:metabolism; D010146:Pain / Q000503:physiopathology*; D051381:Rats; D012684:Sensory Thresholds
D002395:Catecholamines; D009270:Naloxone; D004298:Dopamine; D009638:Norepinephrine