Intrathecal bradykinin administration: opposite effects on nociceptive transmission.
Injected intrathecally, bradykinin (BK) produced either hyperalgesia (0.15 microg) or antinociception (6.0 microg) in rats when thermal noxious stimuli were used. Similarly, des-Arg(9)-BK at the lower dose (0.15 microg) decreased, whereas at the higher dose (6.0 microg) it increased the threshold to thermal noxious stimuli; however, these effects were less pronounced than those of BK. The antinociception induced by BK was abolished by HOE 140, a B(2) receptor antagonist, injected intrathecally at a dose of 1.3 ng and was markedly attenuated by des-Arg(10)-HOE 140, a B(1) receptor antagonist (1.15 ng i.t.). The results obtained in this study showed that--depending on the dose used--BK and des-Arg(9)-BK could produce pro- as well as antinociceptive actions. Both B(2) and B(1) receptors are involved in the action of intrathecally applied BK.
Department of Pharmacodynamics, Medical University of Warsaw, Poland.
Urszula
U
Sot
Krystyna
K
Misterek
Stanislow Witold
SW
Gumułka
Anna
A
Dorociak
D000818:Animals; D001920:Bradykinin / Q000008:administration & dosage* / Q000031:analogs & derivatives*; D004305:Dose-Response Relationship, Drug; D007278:Injections, Spinal / Q000379:methods; D008297:Male; D010147:Pain Measurement / Q000187:drug effects* / Q000379:methods; D017288:Pain Threshold / Q000187:drug effects / Q000502:physiology; D051381:Rats; D017208:Rats, Wistar; D043783:Receptor, Bradykinin B1; D043782:Receptor, Bradykinin B2; D018002:Receptors, Bradykinin / Q000819:agonists / Q000502:physiology; D044005:Tetrahydroisoquinolines
D043783:Receptor, Bradykinin B1; D043782:Receptor, Bradykinin B2; D018002:Receptors, Bradykinin; D044005:Tetrahydroisoquinolines; C078665:HOE 140, desArg(10)-; C065679:icatibant; D001920:Bradykinin