title: Erythrocyte adenosine deaminase, purine nucleoside phosphorylase and phosphoribosyltransferase activity in patients with Down's syndrome.
abstract: The erythrocyte adenosine deaminase, nucleoside phosphorylase, hypoxanthineguanine phosphoribosyltransferase and adenine phosphoribosyltransferase activities and plasma urate concentrations were measured in 20 cases of Down's syndrome and in 20 age- and sex-matched control subjects. The mean erythrocyte adenosine deaminase and adenine phosphoribosyltransferase activities and plasma urate concentrations were significantly higher in Down's syndrome subjects than in controls (p less than 0.001, p less than 0.01 and p less than 0.001, respectively). In all subjects studied there was a positive correlation between the erythrocyte adenosine deaminase activity and plasma urate concentration (r = 0.488, p less than 0.005). The concentrations of the erythrocyte adenine nucleotides, AMP, ADP and ATP, did not differ in Down's syndrome (n = 10) from those of control subjects (n = 10). The results suggest that the increase of plasma urate concentrations is a consequence of the increase in adenosine deaminase activity in Down's syndrome patients.
mesh_terms: D000227:Adenine Nucleotides / Q000097:blood; D000228:Adenine Phosphoribosyltransferase / Q000097:blood*; D000243:Adenosine Deaminase / Q000097:blood*; D000293:Adolescent; D000328:Adult; D002648:Child; D004314:Down Syndrome / Q000201:enzymology*; D004912:Erythrocytes / Q000201:enzymology; D006801:Humans; D007041:Hypoxanthine Phosphoribosyltransferase / Q000097:blood*; D009700:Nucleoside Deaminases / Q000097:blood*; D010430:Pentosyltransferases / Q000097:blood*; D011683:Purine-Nucleoside Phosphorylase / Q000097:blood*; D014527:Uric Acid / Q000097:blood
chemical_list: D000227:Adenine Nucleotides; D014527:Uric Acid; D010430:Pentosyltransferases; D011683:Purine-Nucleoside Phosphorylase; D000228:Adenine Phosphoribosyltransferase; D007041:Hypoxanthine Phosphoribosyltransferase; D009700:Nucleoside Deaminases; D000243:Adenosine Deaminase