Mechanism Studies Of Protective Effect Of Bu YangHuan Wu Decoction On Experimental Cerebral Ischemic Injury

Objective: To investigate the mechanism of BuYangHuanWu Decoction (BYHWD) on experimental focal cerebral ischemic injuryn rats.Methods: It includes: (l)The effect of BYHWD on infarct volume and pathology change of the insult cerebral hemisphere after permanent focal cerebral ischemia in rats. Permanent Focal cerebral ischemia was produced by permanent middle cerebral artery occlusion (MCAO) with a nylon surgical thread inserted through the internal carotid artery in SD rats. Study the behavior changes of rats and infarct volume and pathology morphological changes through image analysis after TTC stain and HE stain of the brain pieces.(2)The effect of BYHWD on cerebral nitric oxide and nitric oxide synthase level during focal cerebral ischemia in rats.The activity of brain nitric oxide and nitric oxide synthase was measured by NO and NOS reagent salver through ultraviolet spectroscopy.(3)The effects of BYHWD on neuronal nitric oxide synthase immunoreactivity after permanent focal cerebral ischemia in rats. The brain neuronal nitric oxide synthase was assayed by SABC immuneohistochemical technique detection in different brain regions and in different time froml to 10 hours after occlusion. (4)The effect of BYHWD on apoptosis of neuronal cells and Caspase-3 transcription level after permanent focal cerebral ischemia in rats'ischemic penumbra.The brain samples were harvested from ischemic penumbra of cortices.Take count of the apoptosis cells after Apoptosis-Hoechst fluorescence stain. The expression of Caspase-3 mRNA was assessed by RT-PCR.Results: (l)The behavior changes of rats after focal cerebral ischemia was no significantly change (p>0.05) between the model groups and the pretreatment groups. The infarct volume of insult cerebral hemisphere increased with the time ahead and pathology morphological changes of insult4cerebral hemisphere also increased after permanent focal cerebral ischemia in rats. The pretreatment BYHWD groups can significantly minished theinfarct volume and ameliorated the pathology changes of the insult cerebral hemisphere. (2)The activity of NOS in the cerebral tissue was increased in the ischemic hemisphere after induction of ischemia especially at 4 hours after the onset of ischemia. BYHWD group significantly decreased compared with cerebral ischemic group (p<0.05), especially at 4 hours after the onset of ischemia. (3)The activity of nNOS in the cerebral tissue was increased with time ahead in the ischemic hemisphere after the onset of ischemia. BYHWD group significantly decreased compared with cerebral ischemic group (p<0.05). And the decreases begin with the onset of ischemia and go ahead with time. (4)In the penumbra regions of permanent ischemia group the apoptosis neuronal cells and the expression level of Caspase-3 mRNA was increased at 24h after the onset of ischemia It showed that BYHWD groups significantly decreasedapoptosis of neuronal cells and the expression of Caspase-SmRNA compared with cerebral ischemic group (p<0.05),however the higher dose group not exceeded lower dose group.Conclusion: (1) BYHWD could significantly minished the infarct volume and ameliorated the pathology morphological changes of the insult cerebral hemisphere (2) BYHWD could significantly restrain the upregulated activity of NOS after focal cerebral ischemia to protect the cerebral ischanic lesion, especially at 4 hours after the onset of ischemia.(3) BYHWD could significantly restrain the upregulated activity of nNOS after focal cerebral ischemia to protect the cerebral ischemic lesion, begin with the onset of ischemia. (4) BYHWD could significantly decreased apoptosis of neuronal cells, the mechanism of its effects maybe restrain the up-regulated expression of Caspase-3mRNA in penumbra region to choke back the apoptosis after focal cerebral ischemia. So the effect of restrain apoptosismight pass through the process of Caspase-3mRNA transcription.