Abstract

Antipyrine (AP) clearance (CL) serves as an index of hepatic mixed microsomal oxidative system (MMOS) function. The MMOS is influenced by various constitutional and environmental factors. To investigate the effects of physical training (PT) and age on the MMOS, we measured salivary AP CL in five young men (YM) aged 25-28 years and five older men (OM) aged 55-73 before and after a 6-week exercise program. Correlation between salivary and plasma AP levels was 0.88. Subjects exercise prescriptions were predicated on results of an initial treadmill stress test, followed by varied dynamic exercise to achieve 80 of their volitional maximal heart rate for 30-45 min thrice weekly. Training effect (TE) was demonstrated by significant increase in exercise duration in YM and OM. YM showed a highly significant increased level of metabolic equivalents (METS) compared to OM both before and after training. PT did not have a statistically significant effect on AP area under the curve (AUC) or CL; however, the trend was for YM to have reduced AUC and increased CL with PT. In conclusion, we were able to demonstrate TE in both YM and OM. The TE in YM appears to be both peripheral and central, affecting the MMOS, whereas in OM the TE is only peripheral. The lack of TE in MMOS in the OM may reflect irreversible changes with aging on hepatic function. Further studies should be conducted with a larger subject population. Verf.-Referat