Inhibition of the respiratory burst in mouse macrophages by ultra-low doses of an opioid peptide is consistent with a possible adaptation mechanism.
The respiratory burst induced by phorbol myristate acetate in mouse macrophages was inhibited by ultra-low doses (10(-15)-10(-13) M) of an opioid peptide [D-Ala2]methionine enkephalinamide. The effect disappeared at concentrations above and below this range. The inhibition approached 50% and was statistically significant (P < 0.001). Increasing the time of the opioid incubation with cells brought about a shift in the maximal effect to lower concentrations of the opioid (from 10(-13) to 5 x 10(-15) M) and led to a decrease in the value of the effect, fully in accord with the previously proposed adaptation mechanism of the action of ultra-low doses.
Efanov
A M
AM
Belozersky Institute of Physico-Chemical Biology, Moscow State University, Russian Federation.
Koshkin
A A
AA
Sazanov
L A
LA
Borodulina
O I
OI
Varfolomeev
S D
SD
Zaitsev
S V
SV
D000222:Adaptation, Physiological; D000818:Animals; D004305:Dose-Response Relationship, Drug; D004744:Enkephalin, Methionine / Q000008:administration & dosage / Q000031:analogs & derivatives* / Q000494:pharmacology; D066298:In Vitro Techniques; D007700:Kinetics; D017737:Macrophages, Peritoneal / Q000187:drug effects* / Q000378:metabolism*; D008297:Male; D051379:Mice; D008808:Mice, Inbred CBA; D016897:Respiratory Burst / Q000187:drug effects*; D013755:Tetradecanoylphorbol Acetate / Q000494:pharmacology
D004744:Enkephalin, Methionine; C022118:enkephalinamide-Met, Ala(2)-; D013755:Tetradecanoylphorbol Acetate