The Protective Effect Of Paeonol Against Hypoxic-Ischemic Brain Damage Of Neonatal Rats

Objective:To explore the protective effect of Paeonol (Pae) against hypoxic-ischemic brain damage(HIBD) of neonatal rats.Methods:36 neonatal SD rats were randomly divided into normal control, shame operation, HIBD and HIBD+Pae groups. The rats in the shame operration group were merely subjected to dissociation of the left carotid artery. The rats in the HIBD group and HIBD+Pae group were subjected to ligation of the left carotid artery, followed by 2 hrs hypoxia exposure. 50mg/kg Paeonol was intraperitoneally given to rats in the HIBD+Pae group before the hypoxia. At the 6th hour after hypoxia, animals were sacrificed. The expression of cleaved caspase-3 in the damaged cortex of rats was assayed by the immunohistochemical staining and the number of necrotic neurons was counted with hematoxylin-eosin(HE) staining.Results:The number of the cleaved Caspase-3 positive cells in the damaged cortex of rats in the HIBD+Pae group[(55.18±4.66)per visual field] was significantly lower than that in the HIBD group[(61.31±6.46)per visual field, t=2.309, p<0.05], while there was not significant deference between the number in the shame operation group [(20.62±4.27)per visual field] and that in the normal control group [(19.82±3.56)per visual field, t=0.432,p> 0.05] and there was significant deference between the number in the HIBD group and that in the normal control group(t=18.085, p<0.01). The percentage of necrotic neurons was decreased in the HIBD+Pae group[(4.10±0.91)%] in comparison with the HIBD group[(6.64±1.11)%, t=5.291, p<0.01].Conclusions:Paeonol may decrease neuronal necrosis and inhibit the expression of cleaved caspase-3 in the cortex of neonatal rats after hypoxic-ischemia so as to take protective effect against hypoxic-ischemic brain damage.