The neurokinin-2 receptor is not involved in the sensitization of primary afferents of the rat knee joint.
Using electrophysiological methods, we aimed in the present study to determine whether the NK(2) receptor is involved in the sensitization of articular afferents of the rat. Impulse activity from 27 single fine nerve fibres innervating knee joints was recorded during non-noxious and noxious joint rotations. Close intraarterial application of the NK(2) receptor agonist [beta-Ala(8)]NKA(4-10) at doses of 0.2-200 nmol did not sensitize the afferents from normal knee joints to mechanical stimuli whereas the application of substance P (20 nmol) increased their mechanosensitivity. These data further support the hypothesis that the NK(2) receptor is not involved in the sensitization of primary afferents in normal knee joints to mechanical stimuli.
Pawlak
Matthias
M
Physiologisches Institut der Universität Würzburg, Röntgenring 9, D-97070 Würzburg, Germany. matthias.pawlak@mail.uni-wuerzburg.de
Schmidt
Robert F
RF
Nitz
Christian
C
Hanesch
Ulrike
U
D000818:Animals; D007719:Knee Joint / Q000294:innervation*; D008297:Male; D008465:Mechanoreceptors / Q000187:drug effects; D009412:Nerve Fibers / Q000502:physiology; D015288:Neurokinin A / Q000031:analogs & derivatives* / Q000494:pharmacology; D009475:Neurons, Afferent / Q000187:drug effects / Q000502:physiology*; D010146:Pain / Q000503:physiopathology; D010446:Peptide Fragments / Q000494:pharmacology; D010812:Physical Stimulation; D051381:Rats; D017208:Rats, Wistar; D018041:Receptors, Neurokinin-2 / Q000819:agonists / Q000187:drug effects / Q000502:physiology*; D012399:Rotation; D013373:Substance P / Q000494:pharmacology
D010446:Peptide Fragments; D018041:Receptors, Neurokinin-2; C064218:neurokinin A (4-10), beta-Ala(8)-; D013373:Substance P; D015288:Neurokinin A