Evidence for neurokinin-3 receptor-mediated tachykinin release in the guinea-pig ileum.
Contraction of longitudinal muscle strips of the guinea-pig ileum induced by the selective NK3 receptor agonist, succ-[Asp6,MePhe8]SP-(6-11) (senktide), were completely inhibited by tetrodotoxin and partially blocked by atropine. The atropine-resistant contraction was markedly reduced if the smooth muscle tachykinin receptors were either desensitized with the selective NK1 agonist substance P methyl ester, or blocked with the tachykinin receptor antagonist [D-Pro4,D-Trp7,9,10]SP-(4-11). These results suggest that activation of NK3 receptors on enteric neurones results in acetylcholine and tachykinin release.
D000818:Animals; D005260:Female; D006168:Guinea Pigs; D007082:Ileum / Q000187:drug effects / Q000294:innervation / Q000502:physiology*; D066298:In Vitro Techniques; D008297:Male; D009474:Neurons / Q000187:drug effects / Q000378:metabolism; D009479:Neuropeptides / Q000378:metabolism*; D010446:Peptide Fragments / Q000494:pharmacology; D018041:Receptors, Neurokinin-2; D017981:Receptors, Neurotransmitter / Q000187:drug effects / Q000502:physiology*; D018039:Receptors, Tachykinin; D013373:Substance P / Q000031:analogs & derivatives / Q000494:pharmacology; D015320:Tachykinins
D009479:Neuropeptides; D010446:Peptide Fragments; D018041:Receptors, Neurokinin-2; D017981:Receptors, Neurotransmitter; D018039:Receptors, Tachykinin; D015320:Tachykinins; D013373:Substance P; C033611:substance P, methyl ester-; C040436:substance P (4-11), Pro(4)-Trp(7,9,10)-