| Aim: Intracerebral hemorrhage(ICH)is a kind of cerebrovascular diseases with high mortality. After bleeding in brain, the constant expansion of hematoma area induces and aggravates brain tissue edema surrounding the hematoma, which in a great part results in neurofunctional impairment. So the patients who suffer from cerebral hemorrhage diseases are usually accompanied with neurofunctional disturbance, and most survivors remain permanence neurofunctional loss. Decreasing secondary neurologic injury has become a critical treatment strategy of intracerebral hemorrhage in clinical practice. At present, the extensively used treat methods consist of routine controlling brain edema with dehydrating agent to cut down intracranial pressure; using plasminogen activator such as recombinant streptokinase and tissue plasminogen activator to dissolve the clots; and carrying out operation to remove the hematoma. Nevertheless, the formation mechanisms of brain edema after hemorrhage are very complicated, and plasminogen activator also enhances the brain injury induced by thrombin when dissolving the clots. Therefore, it is still need to seek for more safe and effective medicine for treating intracerebral hemorrhage.Batroxobin is a monocompoent venin defibrase preparation which extracted from venomin. At home and abroad, batroxobin has been widely applied in clinical thrombolysis treatment in acute cerebral infarction since it went on the market. Not only can it effectively inhibit thrombosis and dissolve the clot by decomposing fibrinogen, inducing endothelial cells to release t-PA and activating plasminogen; but also can reduce brain edema and injury after stroke, having neuroprotective effect.In this study we observed the intervention effect of batroxobin on experimental intracerebral hemorrhage in rats. The aim was to research if batroxobin has the protective effect on cerebral injury caused by hematoma and brain edema surrounding hematoma in intracerebral hemorrhage, and to explore its possible protection mechanismMethod: The rats were divided into sham group, model group, batroxobin small, middle, large dose groups and nimodipine positive control group. On the brain stereotaxic apparatus,the rat intracerebral hemorrhage model was established by injecting collagenase with microinjector into the brain caudate nucleus which was located according to the brain stereotaxic atlas. The sham group rats were only injected saline into the brain caudate nucleus, not bleeding. Medicine was administered intraabdominally at the same time with injecting collagenase in every medication groups. In order to observe the neuroprotective effect of batroxobin on intracerebral hemorrhage rats, neuroethology of the rats was evaluated at four and twenty-four hours after hemorrhage respectively. The water content of the brain tissue was quantitated with wet/dry weight measurement. And the brain tissue pathomorphology was observed in electron microscope by HE dyeing of the brain tissue slice. In order to explore the possible protection mechanism of batroxobin, the level of oxidative stress markers (superoxide dismutase, SOD and malondialdehyde, MDA ) in brain tissue was detected according to the kit procedure. Free Ca2+ concentration([Ca2+]i) in neurocyte was measured by fluorospectrophotometer. And the expression of heme oxygenase-2 (HO-2)and glial fibrillary acidic protein (GFAP)were assessed for the cerebral tissue using SABC (Strept Avidin Biotin Complex) immunohistochemistry.Results:(1)Batroxobin(8, 16 BU/kg)and nimodipine obviously improved the rat neuromuscular function scale at four and twenty-four hours after hemorrhage, reduced brain edema and improved pathological morphology of rat brain after cerebral hemorrhage. Compared with model group, the brain water content in batroxobin 8 BU/kg and 16 BU/kg groups was respectively reduced to 47.4±1.2 and 46.8±1.4 from 49.5 ±1.0, the difference having statistical significance ( P<0.05 ) ; (2) Batroxobin(8,16 BU/kg)significantly increased the activity of SOD, decreased the level of MDA and [Ca2+]i , and down-regulated the expression of HO-2 and GFAP of rats brain after cerebral hemorrhage. Compared with model group, SOD activity, MDA content and [Ca2+]i in batroxobin 8 BU/kg and 16 BU/kg groups was respectively raised to 116.8±19.6 and 126.2±31.4 from 57.4±29.5, reduced to 1.0±0.3 and 0.83±0.2 from 1.4±0.39, and was reduced to 182.7±21.2 and 152.3±12.1from 257.4±35.3, the difference having statistical significance(P<0.05); (3) Batroxobin(4 BU/kg)didn't obviously improve the rat neuromuscular function scale at four hours , reduce brain edema and improve pathological morphology after cerebral hemorrhage, only having a little effect on the rat neuromuscular function scale at twenty-four hours after hemorrhage. Batroxobin(4 BU/kg)didn't also significantly increase the activity of SOD, decrease the level of MDA and down-regulate the expression of HO-2 and GFAP of rats brain after cerebral hemorrhage, but having relatively manifest inhibitory action on [Ca2+]i of rats brain, which [Ca2+]i was 196.0±15.1, the difference having statistical significance(P<0.05)compared with the model group 257.4±35.3.Conclusions:(1)Batroxobin(8,16BU/kg)has evident protective effect on brain tissue damage caused by cerebral hemorrhage in rats; (2)The mechanism of action of batroxobin(8,16BU/kg)maybe relate to reducing the brain tissue water content , MDA level and [Ca2+]i, raising SOD activity and down-regulating the over-expression of HO-2 and GFAP of rats brain after cerebral hemorrhage;(3) Batroxobin(4 BU/kg)has not obvious the protective effect on cerebral hemorrhage in rats, which is possible concerned with its small dosage and low effective concentration. But it is relatively evident in the improvement of rats neuromuscular function scale at twenty-four hours after hemorrhage, the inhibitory action on [Ca2+]i of batroxobin 8 BU/kg is its potential mechanism.
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