Anti-analgesic activity of enterostatin (VPDPR) is mediated by corticosterone.
Although enterostatin (VPDPR) inhibited morphine-induced analgesia, it had no affinity for mu-opioid receptors. VPDPR administration was reported to elevate serum corticosterone levels. We found that corticosterone exhibited a similar anti-analgesic effect selective for mu-opioid. Furthermore, the anti-analgesic effect of VPDPR was inhibited by RU486, an antagonist for the glucocorticoid receptor. The anti-analgesic effect of VPDPR was not observed in adrenalectomized mice. These results suggest that the anti-analgesic activity of VPDPR is mediated by corticosterone released from the adrenal cortex.
Takenaka
Y
Y
Division of Food Science and Biotechnology, Graduate School of Agriculture, Kyoto University, Uji, 611-0011 Kyoto, Japan.
Nakamura
F
F
Usui
H
H
Lipkowski
A W
AW
Toth
G
G
Yoshikawa
M
M
D000701:Analgesics, Opioid / Q000037:antagonists & inhibitors*; D000818:Animals; D001667:Binding, Competitive; D003345:Corticosterone / Q000494:pharmacology*; D004041:Dietary Fats / Q000008:administration & dosage / Q000494:pharmacology; D008297:Male; D051379:Mice; D015735:Mifepristone / Q000378:metabolism; D009020:Morphine / Q000037:antagonists & inhibitors*; D009842:Oligopeptides / Q000378:metabolism / Q000494:pharmacology*; D017473:Receptors, Opioid, kappa / Q000037:antagonists & inhibitors / Q000378:metabolism; D017450:Receptors, Opioid, mu / Q000037:antagonists & inhibitors / Q000378:metabolism
D000701:Analgesics, Opioid; D004041:Dietary Fats; D009842:Oligopeptides; D017473:Receptors, Opioid, kappa; D017450:Receptors, Opioid, mu; C107385:valyl-prolyl-aspartyl-prolyl-arginine; D015735:Mifepristone; D009020:Morphine; D003345:Corticosterone