[Concentration changes of potassium and hypoxanthine in vitreous humor of swine and its application to postmortem interval estimation].

OBJECTIVE

To investigate the relationship between postmortem interval (PMI) and concentration changes of components in swine vitreous humor.

METHODS

Ninety-six porcine eyes from swine dying from acute massive hemorrhage, being randomly divided into 24 groups, were stored in dark situation, at temperature of (15 +/- 2) degrees C and humidity of (50 +/- 5)% for 2-96 hours separately. The vitreous humor was collected. Concentrations of K+, Na+, Cl- and hypoxanthine (Hx) were analyzed by automatic biochemical analyzer and ultra performance liquid chromatograph (UPLC). The data were statistically analyzed by SPSS software.

RESULTS

Linear regression analysis showed that concentrations of vitreous K+ and Hx were positively correlated with PMI(R2=0.767 and R2 = 0.793, respectively). Binary linear regression showed a higher correlation for K+ and Hx with PMI estimation (R2 = 0.866). PMI was not significantly correlated with vitreous Na+ and Cl- concentrations.

CONCLUSION

Vitreous K+ and Hx concentrations can be used as the objective markers for PMI estimation. The binary linear regression functions of vitreous K+ and Hx concentrations with PMI are more accurate for estimating the PMI.