PMID: 6840934Jan 1, 1983Paper

C5a and antigen-induced tracheal contraction: effect of a combination of an antihistamine and cyclo-oxygenase inhibitors

International Journal of Immunopharmacology
J F Regal, R J Pickering


Our previous studies with C5a, a cleavage product of the fifth component of complement, have shown that the antihistamine diphenhydramine and the cyclo-oxygenase inhibitor aspirin do not inhibit the C5a-induced contraction of isolated guinea pig trachea (Regal, Eastman & Pickering, 1980; Regal & Pickering, 1981). We investigated the effect of cyclo-oxygenase inhibitors in the presence of diphenhydramine to determine if cyclo-oxygenase products were contributing to the contraction beyond any effect they might have on histamine release. A combination of a cyclo-oxygenase inhibitor and diphenhydramine caused a delay in onset and decrease in magnitude and duration of the C5a-induced contraction. Indomethacin itself also caused a slight inhibition. In contrast, a combination of aspirin and diphenhydramine did not inhibit the initial portion of antigen-induced tracheal contraction any more than diphenhydramine alone and enhanced the later portion just as aspirin alone. Cross tachyphylaxis experiments demonstrated that antigen pretreatment significantly inhibited a subsequent C5a-induced tracheal contraction, though C5a pretreatment did not affect a subsequent antigen-induced contraction. Thus, cyclo-oxygenase products do contribute t...Continue Reading


Apr 1, 1979·Acta Physiologica Scandinavica·K PavekG Smedegård
Jan 1, 1978·Advances in Immunology·T E Hugli, H J Müller-Eberhard
Mar 1, 1979·British Journal of Pharmacology·T J Williams
Mar 7, 1980·European Journal of Pharmacology·R Levi, J A Burke
Oct 2, 1980·The New England Journal of Medicine·E J Goetzl
Mar 1, 1953·British Journal of Pharmacology and Chemotherapy·J L MONGAR, H O SCHILD
Aug 31, 1959·Acta Physiologica Scandinavica·N CHAKRAVARTY
Sep 1, 1951·British Journal of Pharmacology and Chemotherapy·W D M PATON

Related Concepts

Related Feeds

Alternative Complement Pathway

The Alternative Complement Pathway is part of the innate immune system, and activation generates membrane attack complexes that kill pathogenic cells. Discover the latest research on the Alternative Complement Pathway.