Measurement of adenosine, inosine and hypoxanthine in human term placenta by reversed-phase high-performance liquid chromatography.
An analytical method was developed for measuring adenosine, inosine and hypoxanthine in freshly delivered human term placentas. Representative freeze-clamped samples were taken from the sub-maternal surface of each placenta. Acid-soluble extracts of the samples were analyzed by reversed-phase high-performance liquid chromatography on columns packed with 10-micron porous octadecylsilica, using gradient elution with a linear increase in methanol concentration in ammonium phosphate buffer. Resolution of hypoxanthine from xanthine and adenosine from adenine, and quantitation of hypoxanthine and adenosine were achieved using 0.05 M ammonium dihydrogen phosphate, pH 6.5, as the low-strength eluent. Resolution of inosine from a prominent peak of beta-NAD was optimized using 0.02 M ammonium dihydrogen phosphate, pH 5.6, as low-strength eluent. Recovery of standards was greater than 90%. Mean contents (+/- S.D.) of the analytes in placentas from seven normal deliveries were, adenosine 30.6 +/- 11.5 nmol/g, inosine 68.0 +/- 25.8 nmol/g and hypoxanthine 217 +/- 127.5 nmol/g.
D000241:Adenosine / Q000032:analysis*; D002851:Chromatography, High Pressure Liquid; D005260:Female; D006801:Humans; D019271:Hypoxanthine; D007042:Hypoxanthines / Q000032:analysis*; D007288:Inosine / Q000032:analysis*; D010920:Placenta / Q000032:analysis*; D011247:Pregnancy; D013056:Spectrophotometry, Ultraviolet; D014969:Xanthine Oxidase / Q000378:metabolism
D007042:Hypoxanthines; D019271:Hypoxanthine; D007288:Inosine; D014969:Xanthine Oxidase; D000241:Adenosine