Effect of experimental fasciolosis on antipyrine metabolism and clearance in water buffaloes

The effect of chronic Fasciola hepatica infection on the metabolism of anti pyrine, a marker of microsomal oxidative metabolism, was investigated in ma le water buffaloes dosed daily with 60 F. hepatica metacercariae over 20 da ys. The plasma elimination half-life of antipyrine was significantly elevat ed by 23% at 11 weeks postinfection (p.i.) but did not significantly differ from the control period at 20 weeks p.i. The systemic clearance of antipyr ine decreased by 48% at 11 weeks p.i. and then returned to normal. The rena l clearance for each of the main antipyrine metabolites decreased at 11 wee ks p.i. (hydroxymethylantipyrine (HMA), -42%; norantipyrine (NORA), -58%; a nd 4-hydroxyantipyrine (OHA), -70%) and did not significantly differ from t he control period at 20 weeks p.i. These findings indicate that experimenta l subclinical fasciolosis leads to altered antipyrine kinetics and to an in hibition of the different antipyrine metabolic pathways in water buffaloes. (C) 2000 Elsevier Science B.V. All rights reserved.