VASODILATING PROPERTIES OF A NEW NONSTEROIDAL ANTIINFLAMMATORY DRUG, NITROFLURBIPROFEN, ON RAT AORTIC RINGS

The effects of nitroflurbiprofen (NFP), a new non-steroidal anti-infla mmatory drug containing a nitroxybutyl moiety, on rat aortic rings wer e compared with those of flurbiprofen (FP) and glyceryl trinitrate (GT N). NFP and GTN relaxed, in a dose-dependent manner, either intact or rubbed aortic rings precontracted with epinephrine. Pretreatment with FP did not influence the relaxant activity of NFP in both endothelium- intact and -denuded arteries. In unrubbed preparations, FP did not aff ect contraction induced by epinephrine, while in rubbed ones a moderat e relaxation was observed. Methylene blue and oxyhaemoglobin completel y reversed the vasodilating effect of NFP in both rubbed and unrubbed preparations. Moreover, the addition of cysteine 5 mmol l(-1) at the e nd of the cumulative application of NFP resulted in a further relaxati on of aortic rings. These results indicate that NFP possesses vasodila tory activity which appears to be dependent on the release of nitric o xide or nitric oxide derivatives. (C) 1996 The Italian Pharmacological Society.