Characterization of tachykinin receptors in ferret trachea by peptide agonists and nonpeptide antagonists
Geppetti, P.; Bertrand, C.; Bacci, E.; Huber, O.; Nadel, J.A.
American Journal of Physiology 265(2 Pt 1): L164-L169
1993
ISSN/ISBN: 0002-9513 PMID: 7690189 Document Number: 421836
The tachykinin receptors mediating mucus secretion and smooth muscle contraction were studied in the ferret trachea in vitro. Substance P (SP) and the selective agonist for NK-1 receptor ((Sar-9,Met(O-2)-11)SP), but not selective agonists for NK-2 ((Ala-5,beta-Ala-8)neurokinin A-(4-10)) and NK-3 ((MePhe-7) neurokinin B) receptors, induced secretion of macromolecules in a concentration-dependent fashion. The nonpeptide NK, receptor antagonist, CP96,345, but not the nonpeptide NK-2 receptor antagonist, SR-48968, inhibited SP-induced secretion. Both neurokinin A (NKA) and (Ala-5,beta-Ala-8)NKA-(4-10), but not NK-1 and NK-3 selective agonists, evoked a concentration-dependent smooth muscle contraction. SR-48968, but not CP-96,345, inhibited in a concentration-dependent manner the response to NKA. CP96,345 and SR-48968 did not affect the concentration-dependent increase in macromolecule secretion or smooth muscle contraction by carbachol. These findings indicate that NK-1 receptors mediate secretion of macromolecules and NK-2 receptors mediate smooth muscle contraction, in response to tachykinins in the ferret trachea in vitro.