Ž . European Journal of Pharmacology 331 1997 31–38 Characterization of des-Arg 9 -bradykinin-induced contraction in guinea-pig gallbladder in vitro Daniela A. Cabrini, Joao B. Calixto ) ˜ Department of Pharmacology, Center of Biological Sciences, UniÕersidade Federal de Santa Catarina, Rua Ferreira Lima 82, 88015-420 Florianopolis SC, Brazil Received 6 January 1997; revised 14 May 1997; accepted 16 May 1997 Abstract We have reported that bradykinin induces graded contraction in guinea-pig gallbladder in vitro through activation of bradykinin B 2 receptors and prostanoid release, while des-Arg 9 -bradykinin, a selective bradykinin B receptor agonist, causes only a weak contraction, 1 suggesting the presence of badykinin B receptors in this tissue. In the present study, we attempted to characterise the receptor subtype 1 and the possible mechanism by which des-Arg 9 -bradykinin induces contraction in this preparation. Contractions induced by des-Arg 9 - Ž . bradykinin in guinea-pig gallbladder 1 pM to 1 mM increased significantly as a function of time elapsed after setting up of the Ž . 9 preparation, reaching the maximum after 6 h of equilibration EC 16.4 pM and E 0.6 "0.08 g . Des-Arg -bradykinin-induced 50 max Ž . Ž contraction in guinea-pig gallbladder was totally prevented by cycloheximide 70 mM, an inhibitor of protein synthesis , indomethacin 3 . Ž . Ž . 2q mM , ibuprofen 30 mM , phenidone 30 mM or Ca -free medium plus EGTA, and was partially antagonised by MK 571 ŽŽ Ž Ž Ž . . ŽŽ . . . . 3- 3- 2- 7-chloro-2-quinolinyl ethenyl phenyl 3-dimethyl amino-3-oxo-propyl thio methyl propanoic acid, 0.1 mM or by Ž . Ž . Ž . Ž Ž w Ž . nicardipine 1 mM , but was not affected by dazoxiben 30 mM , staurosporine 100 nM or L 655,240 240 3- 1- 4-clorobenzil -5-flu- x . 9 oro-3-metilhyindol-2il 2,2-dimetilpropanoic acid, 1 mM . Unexpectedly, des-Arg -bradykinin-induced contraction was unaffected by the 9 w 8 x 9 Ž 0 w 3 selective bradykinin B receptor antagonists, des-Arg - Leu -bradykinin and des-Arg -NPC 17761 des-Arg -D-Arg Hip , D-HipE 1 Ž . 7 8 x 9 . Ž 0 w 3 5 transtiofenil , Oic -des-Arg -bradykinin . However, the selective bradykinin B receptor antagonists, HOE 140 D-Arg - Hyp , Thi , 2 7 8 x . Ž 0 w 3 Ž . 7 8 x . 9 D-Tic , Oic -bradykinin and NPC 17731 D-Arg Hyp , DHypE transpropyl , Oic -bradykinin , completely blocked des-Arg - Ž bradykinin-mediated contraction. Pre-treatment of the animals with Escherichia coli endotoxin lipopolysaccharide, 30 mgranimal, i.v., . 9 9 24 h did not significantly change the response to des-Arg -bradykinin induction. It is concluded that des-Arg -bradykinin-induced Ž. contractions in guinea-pig gallbladder are mediated primarily by the release of proinflammatory eicosanoid s derived from the cyclo-oxygenase pathway. These effects are unrelated to thromboxane A and do not seem to be coupled to activation of a protein kinase 2 C-dependent mechanism. Response to des-Arg 9 -bradykinin increases as a function of the equilibration period of the preparation by a Ž . mechanism dependent on protein synthesis and seems to be mediated by activation of bradykinin B but not B receptors. Finally, in 2 1 contrast to that observed for bradykinin, the contraction induced by des-Arg 9 -bradykinin in guinea-pig galbladder is fully dependent on the influx of extracellular Ca 2q , partially through L-type Ca 2q channels. q 1997 Elsevier Science B.V. Keywords: Des-Arg 9 -bradykinin; Gallbladder, guinea pig; Bradykinin B receptor-selective antagonist; Bradykinin B receptor-selective antagonist; 1 2 Prostanoid; Ca 2q 1. Introduction Kinin action is mediated by the activation of two mem- brane receptors, denoted B and B . Bradykinin preferen- 1 2 tially acts through stimulation of constitutive B receptors 2 which are widely distributed in both peripheral and central Ž . nervous systems Hall, 1992 . On the other hand, the kinins without the C-terminal arginine des-Arg 9 -bradykinin ) Ž . Corresponding author. Fax: 55-48 222-4164. or des-Arg 10 -lys-bradykinin, two kininase I active metabo- lites, exhibit higher affinities for the kinin B than B 1 2 Ž . receptor Marceau, 1995 . Much less is known about the bradykinin B receptors than for the B receptors. 1 2 Bradykinin B receptors are rarely expressed in non- 1 traumatized tissues and are up-regulated following in vitro incubation for long periods, after tissue trauma or infection or in vivo following treatment of animals with bacterial Ž lipopolyssacharide endotoxin Regoli and Barabe, 1980; ´ . Bhoola et al., 1992; Burch et al., 1993; Marceau, 1995 . 0014-2999r97r$17.00 q 1997 Elsevier Science B.V. All rights reserved. Ž . PII S0014-2999 97 01010-8