Determination of rat cerebrospinal fluid concentrations of adenosine, inosine, hypoxanthine, xanthine and uric acid by high performance liquid chromatography

Isocratic reverse-phase high performance liquid chromatography techniques were developed to resolve and quantitate the purine nucleosides adenosine (Ado) and inosine (Ino) and their metabolites hypoxanthine (Hyp), xanthine (Xan), and uric acid (UA) in the cerebrospinal fluid of the rat. The moving phase composition for resolving hypoxanthine, xanthine and uric acid was a 0.22 M, pH 5.8 phosphate buffer. The moving phase composition for resolving adenosine and inosine was a 0.22 M, pH 6.8 phosphate buffer, 7% methanol (v/v) and 2.5 mM tetrabutylammonium phosphate. The observed cerebrospinal fluid concentrations in the rat were: Ado = 35 +/- 9 nM (s.e.m.), Ino = 359 +/- 85 nM, Hyp = 243 +/- 77 nM, Xan = 1340 +/- 423 nM and UA = 6130 +/- 678 nM.