Introduction: Paraoxonase (PON1) is one of enzymes participating in antioxidative defence mechanism, which protects the organism from the results of action of reactive oxygen species. PON1 is an esterase contained in plasma high density lipoproteins (HDL) which protects HDL from peroxidation and plasma membranes from free radical injury. PON1 serum activity is diminished in some diseases (atherosclerosis, diabetes, coronary artery disease) and after cardiosurgery operations. But there is no information about changes in PON1 activity after abdominal operations.
The aim: Of this study was the assessment of PON1 serum activity after the abdominal operations in women.
Materials and methods: 40 women operated in the 1st Department of Gynaecology of Lublin Medical University were studied, including 34 patients after total abdominal hysterectomy with salpingo-oophorectomy and 6 patients after myomectomy or cyst enucleation. The blood to experiments was collected before operation, and 8 and 24 hours after. PON1 serum activity was assessed spectrophotometrically toward two synthetic substrates: paraoxon and phenyl acetate.
Results: PON1 activity toward paraoxon before operation was 146.8 +/- 17.3 U/ml, and after 8 and 24 hours after 107.6 +/- 11.9 U/ml and 119.9 +/- 16.9 U/ml, respectively (results statistically significant). PON1 activity toward phenyl acetate (arylesterase activity) before operation was 182.7 +/- 16.4 U/ml and did not significantly changed after the surgery.
Conclusion: It is observed decreased PON1 serum activity in the early postoperative period after abdominal operations in women, what can be connected with the utilisation of PON1 in antioxidative defence mechanism.