Ž . European Journal of Pharmacology 395 2000 247–253 www.elsevier.nlrlocaterejphar Bradykinin potentiates prostaglandin E release in the human gingival 2 fibroblasts pretreated with interleukin-1 b via Ca 2q mobilization Sumi Nakao a , Yorimasa Ogata b , Thomas Modeer c , Shunsuke Furuyama d , Hiroshi Sugiya d, ) ´ a Department of Pharmacology, Nihon UniÕersity School of Dentistry at Matsudo, Matsudo, Chiba 271-8587, Japan b Department of Periodontology, Nihon UniÕersity School of Dentistry at Matsudo, Matsudo, Chiba 271-8587, Japan c Department of Pediatric Dentistry, Karolinska Institutet, Huddinge, Sweden d Department of Physiology, Nihon UniÕersity School of Dentistry at Matsudo, Matsudo, Chiba 271-8587, Japan Received 16 December 1999; received in revised form 21 March 2000; accepted 28 March 2000 Abstract Interleukin-1b, a proinflammatory cytokine, causes a slow increase in prostaglandin E release. On the other hand, bradykinin, a 2 Ž . chemical mediator for inflammation, induces a rapid prostaglandin E release. Simultaneous stimulation with interleukin-1b 200 pgrml 2 Ž . and bradykinin 1 mM evoked a moderately synergistic increase in prostaglandin E release in human gingival fibroblasts. However, in 2 the human gingival fibroblasts pretreated with interleukin-1b, bradykinin drastically enhanced prostaglandin E release. NS-398, a 2 specific inhibitor of cyclooxygenase-2, inhibited not only interleukin-1b-induced prostaglandin E release but also bradykinin-induced 2 prostaglandin E release in the human gingival fibroblasts pretreated with interleukin-1b. Transcriptional and translational inhibitors such 2 as actinomycin D, cycloheximide, and dexamethasone also suppressed the interleukin-1b-induced prostaglandin E release and the 2 bradykinin-induced prostaglandin E release in interleukin-1b-pretreated human gingival fibroblasts. In the fibroblasts pretreated with 2 interleukin-1b, Ca 2q -mobilizing reagents such as ionomycin and thapsigargin mimicked the potentiating effect of bradykinin on prostaglandin E release. These results suggest that interleukin-1b- and bradykinin-induced prostaglandin E release is dependent on 2 2 cyclooxygenase-2 and the potentiated effect of bradykinin in the human gingival fibroblasts primed with interleukin-1b is caused by Ca 2q mobilization. q 2000 Elsevier Science B.V. All rights reserved. Keywords: Bradykinin; Interleukin-1b; Prostaglandin E ; Ca 2q mobilization; Gingival fibroblast, human 2 1. Introduction Prostaglandin E is widely distributed in various organs 2 Ž and exerts effects on various biological activities Shimizu . and Wolfe, 1990 . In inflammation processes, prosta- glandin E is considered likely to play crucial roles, since 2 chemical mediators invoke prostaglandin E synthesis in 2 Ž . Ž fibroblasts Unemori et al., 1994 , endothelial cells Bot- . Ž . toms et al., 1985 , monocytes Nichols et al., 1987 , and Ž . neutrophils Doerfler et al., 1989 at inflammation sites. The rate of production of prostanoids, including prosta- glandin E , is determined in part by the levels of cyclo- 2 oxygenase. Two forms of cyclooxygenase have been char- acterized: a constitutively expressed form, cyclooxy- ) Corresponding author. Tel.: q 81-47-360-9326; fax: q 81-47-360- 9327. Ž . E-mail address: sugiya@mascat.nihon-u.ac.jp H. Sugiya . Ž genase-1, and an inducible form, cyclooxygenase-2 De- . Witt, 1991; Geng et al., 1995 . Cyclooxygenase-1 may be responsible for basal prostanoid biosynthesis and may be necessary for maintenance of physiological functions and cytoprotection. In contrast, cyclooxygenase-2, which is rapidly induced in inflammatory states, may produce the prostanoids involved in immune andror inflammatory re- sponses. Bradykinin is a small peptide with a potent ability to induce pain, vasodilation, and increase of vascular perme- ability, and is implicated in the pathogenesis of inflamma- Ž . tion Regoli and Barabe, 1980 . It has been suggested that proinflammatory properties of bradykinin are mediated by inducing the synthesis and release of arachidonic acid and the prostanoids in a variety of target cells and tissues. We have previously shown that bradykinin rapidly induces prostaglandin E release coupled to Ca 2q influx from an 2 Ž extracellular site in human gingival fibroblasts Yokota et . al., 1994 . In addition, bradykinin stimulated bone resorp- 0014-2999r00r$ - see front matter q 2000 Elsevier Science B.V. All rights reserved. Ž . PII: S0014-2999 00 00262-4