Table 1

Hepatic xanthine oxidase and aldehyde oxidase activity in different species

SpeciesEnzyme Activity Towards1-a: (nmol/mg protein/min)Phthalazine / Phenanthridine / Xanthine
Xanthine (50 μM)Phenanthridine (50 μM)Phthalazine (1 mM)Famciclovir (1 mM)6-Deoxypenciclovir (1 mM)
Human (N = 5)1-b 0.5  ± 0.29.9  ± 2.828.2  ± 8.314.2  ± 3.8 ND1-c 56:20:1
Guinea pig (N = 3–6)10.3  ± 1.649.0  ± 5.4240.1  ± 70.5268.2  ± 52.8156.4  ± 38.223:5:1
AO-active rat (N = 2–10)28.5  ± 1.828.0  ± 1.7113.7  ± 14.4 32 134:1:1
AO-deficient rat (N = 2–15)20.9  ± 1.50.0 <0.6 NR1-d 0.1  ± 0.1
Rabbit (N = 2–3)14.0100.9  ± 14.2426.522513031:7:1
  • 1-a The figures are expressed as mean ± SEM.

  • 1-b The values in brackets represent the number of different liver samples employed.

  • 1-c Not determined.

  • 1-d No reaction.