The effect ofmisoprostol, a synthetic analogue of prostaglandin E, on prostalandin concentrations in synovial fluids was investigated in a randomised placebo controiled, double blind study. The synovil fluid concentrations of prostaglandin E1, 6-keto-prostaglandin Flag and thromboxane B2 were measured at the beginning and end of a 24 hour period in 25 patients with effusions of the knee joint. During this period the patients were treated with diclofenac (50 mg every eight hours) and either misoprostol (400 pAg) or After an initial drug washout period of at least three days, during which paracetamol was provided for the relief of pain, the patients were randomly allocated to treatment with either misoprostol or a placebo. The two groups received diclofenac (50 mg) at time 0, 8 and 16 hours, with either misoprostol (400 [Lg) at time 0 and 12 hours, or matching placebo. The study was double blind in design with all preparations given by mouth.The presence or absence of clinical signs of inflammation (warmth, tenderness, synovial thickening) was recorded for both knees at the beginning and end of the study period.At time 0 and 24 hours synovial fluid was aspirated from the same knee without the use of local anaesthesia. Between two and four millilitres, of the synovial fluid was immediately mixed with 0-05 ml of 0-2% indomethacin in a glass tube, then frozen and stored at -20°C until required. The prostaglandin E series was measured by assaying the stable metabolite 11-deoxy-13,14-dihydro-15-keto-11,16-cycloprostaglandin E2 and the analogous E1 metabolite, prostacyclin was assayed as 6-ketoprostaglandin Fla, and thromboxane as thromboxane B2 using radioimmunoassay kits supplied by Amersham (TRK 800, RPA 515 and RPA 516, respectively) with the methods described in the accompanying data sheets. All the assay procedures were validated before this study. Synovial fluid samples were assayed in five batches, the two samples from a given patient beingassayed in the same batch.
STATISTICALMETHODSOwing to the distributional form of the results of the prostaglandin assay, analyses were performed on the logarithms of the data. The treatments were compared by the analysis of 797 on 11 May 2018 by guest. Protected by copyright.