ORIGINAL ARTICLES   

The Journal of Sports Medicine and Physical Fitness 1999 September;39(3):197-201

Copyright © 2000 EDIZIONI MINERVA MEDICA

language: English

Changes in metabolism and urinary excretion of antipyrine induced by aerobic conditioning

Villa J. G. ¹, Bayon J. E. ², Gonzales-Gallego J. ²

¹ Institute of Physical Education, University of León, León, Spain; ² The Department of Physiology, Pharmacology and Toxicology, University of León, León, Spain

Background. Physical con­di­tion­ing has ­been report­ed to ­increase liv­er oxi­da­tive metab­olism deter­mined by anti­py­rine clear­ance. The pur­pose of ­this inves­ti­ga­tion was to ­study ­effects of aero­bic con­di­tion­ing on the dif­fer­ent meta­bol­ic path­ways of anti­py­rine by com­par­ing the pro­duc­tion clear­anc­es of anti­py­rine metab­olites.
Methods. Participant: vol­un­teers not ­engaged in the system­at­ic prac­tice of any ­sport (n=14) ­were com­pared ­with ae­rob­i­cal­ly-con­di­tioned sub­jects (n=14) (­long dis­tance run­ners, ­defined as men run­ning >80 km/­week). Interventions: anti­py­rine was admin­is­tered oral­ly. Saliva sam­ples ­were col­lect­ed ­under ­basal con­di­tions and at 8, 16, 24, 32 and 40 hrs fol­low­ing anti­py­rine admin­is­tra­tion. Urine was col­lect­ed for 24 hrs ­after anti­py­rine inges­tion. Measures: endu­rance per­for­mance was ­expressed by the max­i­mal oxy­gen ­uptake (V.O2max), the ven­til­a­to­ry thresh­old and the 4 mM·l-1 lac­tate thresh­old (­OBLA). Antipyrine phar­ma­cok­i­net­ic param­e­ters (anti­py­rine clear­ance and ­half-­live) ­were ­obtained ­from sali­va sam­ples by the stan­dard mul­ti­ple-sam­ple meth­od.
Results. V.O2max, ven­til­a­to­ry thresh­old and ­OBLA ­were high­er in ­trained ­than in con­trol sub­jects (+32%, +16% and +74%, respec­tive­ly). Salivary anti­py­rine clear­ance was high­er, wheth­er or not ­this var­i­able was cor­rect­ed for ­weight (+26% and +38%, respec­tive­ly), and anti­py­rine ­half-­life was sig­nif­i­cant­ly ­reduced (-31%) in run­ners. There was no sig­nif­i­cant ­change ­with train­ing in the ­renal clear­ance of anti­py­rine or in the noran­tip­y­rine (­NORA) for­ma­tion clear­ance but sig­nif­i­cant increas­es ­were ­observed in hydrox­y­meth­y­lan­tip­y­rine (HMA) and 4-hydrox­yan­tip­y­rine (OHA) for­ma­tion clear­anc­es (+42 and +37%, respec­tive­ly).
Conclusions. The find­ings indi­cate ­that aero­bic con­di­tion­ing ­leads to ­increased dis­po­si­tion of anti­py­rine and ­that the ­main meta­bol­ic path­ways of the com­pound are ­changed dif­fer­ent­ly.