Determination of hipoxanthine and hypoxanthine-guanine phosphoribosyltransferase concentrations in venuos blood of 100 and 400 m runners

Hipoksantin je purinska baza, ki nastane z razgradnjo adenozin trifosfata, iz mišic se izloča v kri. Encim hipoksantin-gvanin-fosforibozil-transferaza, pretvori hipoksantin v inozin monofosfat, iz katerega lahko ponovno nastane adenozin trifosfat. Gre za sistem, ki je pomemben pri regeneraciji adenozin trifosfata, tako med fizično aktivnostjo kot po njej. Najbolj dejaven naj bi bil po visokointenzivnem naporu. Vrednosti hipoksantina bi lahko služile kot metabolni kazalnik in nam pokazale, kako dobro je organizem prilagojen na fizični napor. Meritve hipoksantina in encima hipoksantin-gvanin-fosforibozil-transferaze, bi zato lahko bile v veliko pomoč športnim trenerjem pri načrtovanju treningov. V magistrskem delu smo izmerili celokupne koncentracije hipoksantina in ksantina ter encima hipoksantin-gvanin-fosforibozil-transferaze v venski krvi pri desetih tekačih na 100 in 400 metrov, v različnih obdobjih tekmovalne sezone. Celokupne koncentracije hipoksantina in ksantina smo določili s specifično oksidacijo, koncentracije hipoksantin-gvanin-fosforibozil-transferaze pa s sendvič ELISA. Prav tako smo izmerili še nekatere druge parametre fizične pripravljenosti, ki so nam služili kot pomoč pri razlagi rezultatov meritev venske krvi. Ugotovili smo, da imajo tekači na 100 metrov višje vrednosti celokupnih koncentracij hipoksantina in ksantina v mirovanju in po obremenitvi. Ko smo te rezultate primerjali z rezultati drugih testov za ugotovitev fizične pripravljenosti smo zaznali, da izboljšanju rezultatov pri testu na kolesu sledi znižanje celokupnih koncentracij hipoksantina in ksantina v venski krvi tekačev na 100 metrov in obratno. Prav tako je bilo tudi pri meritvi skoka iz polčepa v zimskem tekmovalnem obdobju. Pri skupini tekačev na 400 metrov se rezultati meritev za ugotavljanje fizične priprave niso bistveno spreminjali skozi sezono in se zato po vsej verjetno tudi celokupne koncentracije hipoksantina in ksantina niso spreminjale. Zaključimo lahko, da morebiti obstaja povezava med celokupnimi koncentracijami hipoksantina in ksantina ter tekmovalno uspešnostjo in da je trend rezultatov takšen, da bi lahko bila celokupna koncentracija hipoksantina in ksantina metabolni kazalnik fizične pripravljenosti.Hypoxanthine is a purine base, which is produced with hydrolysis of adenosine triphosphate. Hypoxanthine efflux from muscles into blood, but it can be recycled via salvage pathway with hypoxanthine-guanine phosphoribosyltransferase, both in muscle and blood. Hypoxanthine-guanine phosphoribosyltransferase convertes hypoxanthine to inosine monophosphate, which is then used to synthetise adenosine triphosphate. This system is very important for adenosine triphosphate energy regeneration during and post exercise. High activity of hypoxanthine-guanine phosphoribosyltransferase is monitored after high intensity exercise. Hypoxanthine can be used as a metabolic indicator of training status and can tell us how well is individual organism adaptated to specific exercise. Because of this, measurement of hypoxanthine and hypoxanthine-guanine phosphoribosyltransferase activity can be used as a aid to track and field and other sport coaches to monitor their athletes adaptation to trainings. We examined ten track and field athletes who competes in 100 meters and 400 meters. We took venous blood samples in different periods of one year competition cycle of athletes. Whole concentrations of hypoxanthine and xanthine were assessed by specific oxidation, and hypoxanthine-guanine phosphoribosyltransferase activity with sandwich ELISA. We also performed other tests to assessed parameters of physical performance of athletes, which helped us to better understand results of concentrations of hypoxanthine and xanthine and hypoxanthine-guanine phosphoribosyltransferase measurements. The results shows that group of athletes who competes in 100 meters have higher values of hypoxanthine and xanthine pre and post exercise during all periods of one year competition cycle. Comparing this results with results of test on the special bike, we find out that higher values of maximal relative peak power leads to lower hypoxanthine and xanthine concentrations and vice versa, for athletes who compete in 100 meters. This also came out in squat jump test for winter competition period. In group of athletes who competes on 400 meters, results of test did not vary so much between competition periods, and then also whole concentrations of hypoxanthine and xanthine are almost the same in whole year. We might conclude that maybe there is possible correlation between hypoxanthine and xanthine concentrations and athletics performance and therefore it can be metabolic indicator that show us how well the human organism is adapted to physical exercise