ABSTRACT
A rapid and sensitive method for the quantitation of buspirone in human plasma by liquid chromatography/electrospray ionization tandem mass spectrometry (LC/ESI-MS/MS) was developed. Plasma samples were treated by liquid-liquid extraction with methyl tert-butyl ether (MTBE). The chromatographic separation was performed isocratically on a reversed-phase Shiseido C18 column (50 mm x 2.0 mm, 3 microm) with a mobile phase of acetonitrile/0.1% acetic acid (1:1, v/v). The acquisition was performed in multiple reaction monitoring (MRM) mode, monitoring the transitions m/z 386 --> 122 for buspirone and m/z 409 --> 238 for amlodipine (the internal standard). The method was validated to determine its specificity, recovery, limit of quantitation, accuracy and precision. The lower limit of quantitation was 0.02 ng/mL with a relative standard deviation of less than 10%. The present method provides an accurate, precise and sensitive tool for buspirone and was successfully applied to a pharmacokinetic study in eight subjects.
Subject(s)
Anti-Anxiety Agents/blood , Anti-Anxiety Agents/pharmacokinetics , Buspirone/blood , Buspirone/pharmacokinetics , Adult , Amlodipine/blood , Area Under Curve , Calcium Channel Blockers/blood , Calibration , Chromatography, Liquid , Half-Life , Humans , Indicators and Reagents , Male , Quality Control , Reference Standards , Reproducibility of Results , Solvents , Spectrometry, Mass, Electrospray Ionization , Tandem Mass SpectrometryABSTRACT
In the present study, syringin, isolated by activity-guided fractionation of the ethyl acetate (EtOAc) extracts of the stem bark of Magnolia sieboldii, and sinapyl alcohol, the hydrolysate of syringin, were evaluated for anti-inflammatory and antinociceptive activities. Sinapyl alcohol (20, 30 mg/kg/day, p. o.) inhibited increased vascular permeability by acetic acid in mice and reduced acute paw edema by carrageenan in rats more so than syringin. When analgesic activity was measured using the acetic acid-induced writhing test and the hot plate test, sinapyl alcohol was much more potent than syringin in a mouse model. In addition, sinapyl alcohol more potently inhibited lipopolysaccharide (LPS)-induced nitric oxide (NO), prostaglandin E2 (PGE2), and tumor necrosis factor (TNF)-alpha production by macrophages than syringin. Consistent with these observations, the expression levels of inducible NO synthase (iNOS) and cyclooxygenase (COX)-2 was reduced by sinapyl alcohol in a concentration-dependent manner. These results suggest that the anti-inflammatory and antinociceptive effects of syringin after oral administration may be attributed to its in vivo transformation to sinapyl alcohol.
