A simple, accurate and fast vortex-assisted dispersive liquid-liquid microextraction procedure has been developed for the extractive spectrophotometric determination of niflumic acid in biological samples. The method is based on the formation of an ion association complex between niflumic acid and methylene blue. The resulting ion-pair was extracted into dichloromethane and its absorbance was m...

Niflumic acid is a noncompetitive inhibitor of chloride exchange, which binds to a site different from the transport or modifier sites. When the internal Cl- concentration is raised, at constant extracellular Cl-, the inhibitory potency of niflumic acid increases. This effect cannot be attributed to changes in membrane potential, but rather it suggests that niflumic acid binds to the anion exch...

The chloride channel antagonists anthracene-9-carboxylic acid, ethacrynic acid and niflumic acid were found to be fungistatic and morphogenic when tested against the ascomycete Neurospora crassa. Potency increased with decreasing pH, suggesting that the protonated forms of the compounds were active. Niflumic acid produced the most pronounced growth aberrations which may reflect an ability to ac...

ATP is an efficacious secretagogue for mucin and chloride in the epithelial cell line HT29-Cl.16E. Mucin release has been measured as [3H]glucosamine-labeled product in extracellular medium and as single-cell membrane capacitance increases indicative of exocytosis-related increases in membrane area. The calcium-activated chloride channel blocker niflumic acid, also reported to modulate secretio...

We investigated the effects of the Cl- channel blockers niflumic acid, 5-nitro-2-(3-phenylpropylamino)-benzoic acid (NPPB) and 4, 4'-diisothiocyanatostilbene-2,2'-disulphonic acid (DIDS) on endothelin-1 (ET-1)-induced constriction of rat small pulmonary arteries (diameter 100-400 microm) in vitro, following endothelium removal. ET-1 (30 nM) induced a sustained constriction of rat pulmonary arte...

BACKGROUND AND OBJECTIVE Results from a relatively small case-control study recently showed that niflumic acid increases the risk of serious mucocutaneous reactions in children. As a consequence, the Italian Ministry of Health sent a "Dear Doctor" letter in June 2001 to warn pediatricians about the alleged adverse effects. The objective of this study was to estimate and compare the incidence of...

Slo2.1 channels conduct an outwardly rectifying K(+) current when activated by high [Na(+)](i). Here, we show that gating of these channels can also be activated by fenamates such as niflumic acid (NFA), even in the absence of intracellular Na(+). In Xenopus oocytes injected with <10 ng cRNA, heterologously expressed human Slo2.1 current was negligible, but rapidly activated by extracellular ap...

The aim of this study was to produce niflumic acid nanoparticles without using an organic solvent, in order to achieve an increased rate of dissolution of the final products. Co-grinding with excipients was used to decrease the particle size. Poloxamer 188 (P) and mannitol (M) applied as co-grinding materials stabilized the system, preventing aggregation of the nanocrystals. The morphology and ...