Background: The maximal physical exercise influences on changes in GH, IGF-1 concentrations and activity of CYP1A2. The aim of this study was to answer the question whether the change of endogenous GH and IGF-1 influenced the expression of CYP1A2 and whether these changes correlate with others parameters of blood and test.
Methods: The twenty ice young hockey players were subjected to maximal exercise cycle test. The test duration was mean 21.0 ± 2.4 min, and work done was mean 3261.3 ± 558.3 J/kg. In blood samples collected before and after the exercise were evaluated: concentrations of GH and IGF-1 which were determined in the serum by IRMA method and the transcriptional activity of CYP1A2 in RNA isolated from whole blood by the QRT-PCR reaction.
Results: Before the exercise the median of GH was mean 0.31 ± 0.23 μU/mL and after the exercise increased to mean 21.6 ± 16.6 μU/mL (P<0.001). Mean of serum IGF-1 level before the exercise and immediately after test did not change. Statistically significant increase in value of Ct for CYP1A2 (P<0.001) was found.
Conclusion: The results of the study showed that: an intense exercise of young ice hockey players led to a significant increase in GH concentration, which caused the Ct values of CYP1A2 increase, whereas IGF-1 did not change. GH and IGF-1 levels after the exercise depended on the work done and the relative levels of CYP1A2 expression correlated with the time and the amount of work done by the athletes.