title: Effect of aspirin on urinary excretion of 6-ketoprostaglandin F1 alpha.
abstract: 1. We studied the effect of oral administration of acetylsalicylic acid (1200 mg/day for 3 days) on the urinary excretion of 6-ketoprostaglandin F1 alpha in normal human subjects as an index of prostacyclin production in vivo. 2. The concentrations and excretion rate in urine fell to 45% of pretreatment levels in 3 days, but returned to pretreatment values after 7 days. 3. These results suggest that production of prostacyclin in vivo is only partially inhibited by high doses of aspirin and that there are sites of production of prostacyclin which are protected from inhibition by aspirin and which contribute to urinary 6-ketoprostaglandin F1 alpha. The measurement of 6-ketoprostaglandin F1 alpha in urine may therefore be of only limited value as an index of the metabolism of vascular tissue in vivo.
mesh_terms: D015121:6-Ketoprostaglandin F1 alpha / Q000652:urine*; D001241:Aspirin / Q000494:pharmacology*; D004305:Dose-Response Relationship, Drug; D006801:Humans; D008297:Male; D013997:Time Factors
chemical_list: D015121:6-Ketoprostaglandin F1 alpha; D001241:Aspirin