Effects of phentolamine and propranolol on the changes of pain threshold and contents of MEK and LEK in rat brain after EA.
The contents of Met-enkephalin (MEK) and Leu-enkephalin (LEK) in striatum and MEK in hypothalamus of rat increased markedly after electroacupuncture analgesia (EAA). Intraperitoneal injection of phentolamine, a blocker of alpha receptor, potentiated the EAA and abolished the effects of EA increasing MEK and LEK contents; while injection of propranolol, a blocker of beta receptor, partially inhibited the EAA, as well as abolished the effects of EA increasing MEK and LEK concentrations in the striatum and the hypothalamus, and also elevated the MEK and LEK contents in hippocampus and MEK level in cortex. The results indicate that EA regulates metabolism of MEK and LEK, as well as EAA partially via alpha and beta receptors.
Wang
Y J
YJ
Wang
S K
SK
D000818:Animals; D001921:Brain / Q000378:metabolism*; D015671:Electroacupuncture; D004743:Enkephalin, Leucine / Q000378:metabolism*; D004744:Enkephalin, Methionine / Q000378:metabolism*; D008297:Male; D010146:Pain / Q000503:physiopathology*; D010646:Phentolamine / Q000494:pharmacology*; D011433:Propranolol / Q000494:pharmacology*; D051381:Rats; D012684:Sensory Thresholds / Q000187:drug effects
D004744:Enkephalin, Methionine; D004743:Enkephalin, Leucine; D011433:Propranolol; D010646:Phentolamine