[Effect of diazoxide on oxygen free radicals and cell apoptosis in brain tissue after deep hypothermia cerebral ischemia reperfusion injury in young rats].

OBJECTIVE

To determine the effects of diazoxide on oxygen free radicals and cell apoptosis in brain tissue after deep hypothermia cerebral ischemia reperfusion injury in young rats.

METHODS

Fifty-four 3-week-old Sprague-Dawley rats were randomly and equitably divided into sham-operated group, model group and diazoxide group respectively (n = 18). The model of hypothermia cerebral ischemia reperfusion injury was made. After 24 hours of operation, the brains of rats were removed and preserved. The content of superoxide dismutase (SOD) and malonaldehyde (MDA) in brain tissue were detected. Cytosolic C release of cytochrome was confirmed by Western Blot. The protein expression of Caspase-3 was determined by immunohistochemistry.

RESULTS

In the model group, the content of SOD was (198 +/- 41) U/mg, lower than the sham-operated group's (321 +/- 36) U/mg (P < 0.01). The content of MDA was (212 +/- 21) nmol/mg, was higher than the sham-operated group's (100 +/- 23) nmol/mg (P < 0.01), and the expressions of cytochrome C (0.72 +/- 0.09) and Caspase-3 (83 +/- 10) were all significantly higher than those in the sham-operated group (0.17 +/- 0.02 and 115 +/- 9) (P < 0.01). Compared with the model group, the content of SOD in the diazoxide group [(264 +/- 34) U/mg] was markedly increased (P < 0.05). In addition, diazoxide provided significant reductions in the content of MDA [(174 +/- 19) nmol/mg] and the expressions of cytochrome C (0.41 +/- 0.05) and Caspase-3 (99 +/- 11) (P < 0.05).

CONCLUSIONS

The neuroprotective effects of diazoxide against brain injury induced by deep hypothermia cerebral ischemia reperfusion through inhibiting oxygen free radicals and cell apoptosis. Diazoxide may become a new neuroprotective drug after infant complicated congenital cardiac operation.