Bradykinin induces a vapid cyclooxygenase-2 mRNA expression via Ca2+ mobilization in human gingival fibroblasts primed with interleukin-1β

We have previously demonstrated that bradykinin potentiates prostaglandin E, release in human gingival fibroblasts pretreated with interleukin-1 beta (priming), In this study, we demonstrate a potentiating effect of bradykinin on cyclooxygenase-2 mRNA expression in the interleukin-1 beta -primed fibroblasts. Interleukin-1 beta (200pg/ml) induced cyclooxygenase-2 mRNA expression, but not bradykinin (1 CIM). However, bradykinin rapidly and markedly increased the cyclooxygenase-2 mRNA expression in the fibroblasts primed with interleukin-1 beta. In the primed fibroblasts, ionomycin and thapsigargin mimicked the potentiating effect of bradykinin on the cyclooxygenase-2 mRNA expression. Dexamethasone and actinomycin D completely suppressed not only the interleukin-1 beta -induced cyclooxygenase-2 mRNA expression, but also the bradykinin-induced cyclooxygenase-2 mRNA expression in the interleukin-1 beta -primed fibroblasts, although cycloheximide did not inhibit the effects of interleukin-1 beta and bradykinin. These results suggest that bradykinin-induced prostaglandin E, synthesis is regulated at the level of the transcription of cyclooxygenase-2 mRNA via Ca2+ mobilization in the interleukin-1 beta -primed human gingival fibroblasts. (C) 2001 Harcourt Publishers Ltd.