Bradykinin increases intracellular calcium levels in a human bronchial epithelial cell line via the B2 receptor subtype.
OBJECTIVE
To determine which types of kinin receptor are present in human bronchial epithelial cells we studied the capability of bradykinin to mobilize intracellular Ca2+ ([Ca2+]i) in a human bronchial epithelial cell line (16HBE cells).


METHODS
Human bronchial epithelial cell line transformed with an original defective simian virus 40 (SV40).


METHODS
Bradykinin (0.1 pM to 0.1 microM), des-Arg9 bradykinin (1 microM), des-Arg10) kallidin (1 microM), indomethacin (1 microM), phosphoramidon (1 microM), captopril (1 microM), des-Arg9-[Leu8]bradykinin (1 microM), HOE 140 (DArg-[Hyp3, Thi5, DTic , Oic8]-bradykinin) (1 microM), and NPC 16731 (DArg-[Hyp3, Thi5, DTic7, Tic8]-bradykinin) (1 microM).


METHODS
The mobilization of [Ca2+]i was determined by the fura-2 method. Two sample Wilcoxon rank-sum (Mann-Whitney) test was used for statistical calculations.


RESULTS
Bradykinin, but not the selective agonists for kinin B1 receptor des-Arg9 bradykinin and des-Arg10 kallidin, increased the mobilization of [Ca2+]i (EC50, 0.079+/-0.009nM) in 16HBE cells in a concentration-dependent manner. Pretreatment with the cyclooxygenase inhibitor indomethacin (1 microM) or the peptidase inhibitors, phosphoramidon (1 microM) or captopril (1 microM), did not affect the response to bradykinin. The kinin B1 receptor antagonist, des-Arg9-[Leu8]bradykinin (1 microM), was inactive. HOE 140 and NPC 16731, two selective antagonists of the kinin B2 receptor abolished the response to bradykinin (IC50 of HOE 140 and NPC 16731 were 0.52+/-0.037nM and 1.67 +/- 0.41 nM, respectively).


CONCLUSIONS
The present data indicate the presence of kinin B2 receptors in the 16HBE cells.
Ricciardolo
F L
FL
Institute of Respiratory Disease, University of Catania, Italy. fricciardo@Pulmonology.azl.nl
Lovett
M
M
Halliday
D A
DA
Nadel
J A
JA
Kaneko
T
T
Bunnett
N W
NW
Geppetti
P
P
D000806:Angiotensin-Converting Enzyme Inhibitors / Q000494:pharmacology; D001920:Bradykinin / Q000494:pharmacology*; D065168:Bradykinin Receptor Antagonists; D001980:Bronchi / Q000187:drug effects / Q000378:metabolism*; D002118:Calcium / Q000378:metabolism*; D002216:Captopril / Q000494:pharmacology; D002461:Cell Line, Transformed; D016861:Cyclooxygenase Inhibitors / Q000494:pharmacology; D004847:Epithelial Cells / Q000187:drug effects / Q000378:metabolism; D006020:Glycopeptides / Q000494:pharmacology; D006801:Humans; D007213:Indomethacin / Q000494:pharmacology; D011480:Protease Inhibitors / Q000494:pharmacology; D043782:Receptor, Bradykinin B2; D018002:Receptors, Bradykinin / Q000502:physiology*; D013539:Simian virus 40
D000806:Angiotensin-Converting Enzyme Inhibitors; D065168:Bradykinin Receptor Antagonists; D016861:Cyclooxygenase Inhibitors; D006020:Glycopeptides; D011480:Protease Inhibitors; D043782:Receptor, Bradykinin B2; D018002:Receptors, Bradykinin; D002216:Captopril; D001920:Bradykinin; D002118:Calcium; C008890:phosphoramidon; D007213:Indomethacin