[Tolerance enhancement on the liver ischemia-reperfusion injuries in rats by ethanol pretreatment]

To investigate the feasibility and efficacy of the ethanol pretreatment. Study was designed to confirm the proper range of the ethanol according to the toxicity and mortality, and then evaluate the possibility of application of the ethanol pretreatment.

(1) Thirty six male adult wistar rats pretreated with 40% ethanol were divided randomizely into six groups by different dosage: group A (8 g/kg), group B (7 g/kg), group C (6 g/kg), group D (5 g/kg), group E (4 g/kg), normal control group (0 g/kg). The safe dosage range of ethanol in rats was predicted by the observation of the symptoms after ethanol administration and pathological changes after 24 h. (2) Based on the results of experiment (1), this experiment were set as follows: 78 wistar rats were divided randomizely into 4 groups: normal control group, ethanol group, ischemia/reperfusion group (IR), ethanol pretreatment group (EP), in each group, the specimen were harvested from the rats at 3, 6, 12, 24 h after reperfusion and then were determined by different methods. (3) Based on the three variant factors (concentration, dosage and proper time for ethanol pretreatment), a orthogonal test were designed to optimize the ethanol pretreatment. 54 wistar rats used in this step were all subjected to hepatic schema procedure for 90 min and the specimens were harvested at 24 h after reperfusion.

Less than 5 g/kg ethanol is safe to the rat, and it can reduce the 90 minutes IR injuries to the liver. Under the mode of A1B1C3, the more protection can be got for hepatic ischemia/reperfusion injuries.

Proper dose of ethanol gavages to the rat is a safe pretreatment method, it maybe enhance the tolerance of rat liver to the I/R injuries.