| Objective: To observe the expression of protein kinase C(PKC), neuronal apoptotic cell, nitric oxide (NO) and tumor necrosis factor-α(TNF-α) in rats after cerebral hemorrhage and the effect of polymyxin B on the above influence. Thus further elucidate the injury mechanism of intracerebral hemorrhage and it's possible measures to protect brain cell. That will provide a theoretical basis for the clinical treatment of cerebral hemorrhage by using Polymyxin B. Methods: 1.Autologous blood was injected into the caudate nucleus of rat that produced cerebral hemorrhage model by using stereotaxis instrument technique. 2.100 SD rats were randomly divided into 4 groups, which were sham operation group(n=25), ICH group(n=25), low dose polymyxin B treatment group (n=25), high dose polymyxin B treatment group (n=25). 3.Intervention methods: Low dose polymyxin B group were injected polymyxin B (0.4mg/kg.d) into the abdominal cavity at 2hr after ICH onset, from then on once 12hr. High dose polymyxin B group were injected polymyxin B (0.8mg/kg.d), from then on once 12hr. The ICH animals recein equivalent amount of sterile saline at the same time. In addition to surgical procedures, the sham operation group did't inject autologous blood, and the other conditions were fully consistent with the ICH group. 4. Decapitation was at 6hr, 12hr, 24hr, 72hr, 120hr after the model was produced, and there were five animals in each group. 5.Brain tissue was homogenated and dehydrated, then made into paraffin block step by step. Immunohistochemistry and TUNEL stain after serial sections, brain tissue used nitrate reductase method, Radioimmunoassay with TNF-α. Then observed the sectiones, took photoes and measured positive cells under microscope. 6.Results were analyzed statistically by SPSS13.0. Results: 1.There was only a few PKC expression in sham operation group and difficult observated apoptotic cell (TUNEL positive cell). 2.PKC isozyme was a great quantity expression in intracerebral hemorrhage group, mainly distributed hematoma perienchyma. PKC expression was onset raise at 6hr, then was evident at 24hr, and reached a high level at 72hr and descented to normal level at 120hr. 3.In intracerebral hemorrhage group, TUNEL cell was expressed from 6hr in hematoma perienchyma, peak at 72hr, and still a higher level at 120hr. 4.NO contents was raise from 6hr in hematoma perienchyma, peak at 72hr, and still a high level at 120hr. 5.TNF-αcontents was raise from 6hr in hematoma perienchyma, peak at 72hr, and still a high level at 120hr, degression was unmanifest. 6.Linear correlation: PKC was siginificantly positively correlated with apoptotic cell (r=0.842,P=0.000<0.05), NO content (r=0.783, P=0.000<0.05) and TNF-αcontent (r=0.664, P=0.001<0.05) in hematoma perienchyma. Low dose polymyxin B group of PKC was siginificantly positively correlated with apoptotic cell (r=0.774, P=0.000<0.05), NO content(r=0.814,P=0.000<0.05) and TNF-αcontent (r=0.605,P=0.005<0.05) in hematoma perienchyma. 7.When polymyxin B was used, the expression of these four targets were decreased from 6hr after intracerebral hemorrhage, and significant mostly at own peak time. 8.Dose had no significant difference in Low dose and high dose polymyxin B group. Conclusions: 1.The ICH models of rat was made by autologous blood that was simple, made easily and had a high achievement ratio. 2.Experimental intracerebral hemorrhage can induce upregulation of PKC expression around the hematoma perienchyma, the mechanism is still not very clear, it may be related to ischemia, hypoxia, reperfusion and so on. 3. PKC, apoptotic cell, TNF-αand NO in the brian hematoma perienchyma markedly increased after ICH, which showed they took part in the pathophysiological process of the secondary damage after ICH. 4.PKC was activated after ICH. PKC was siginificantly positively correlated with apoptotic cell, NO content and TNF-αcontent in hematoma perienchyma after ICH. 5.polymyxin B can significantly reduce the activation of PKC, the mechanism may be related to inhibit the expression of PKC, reduce apoptosis cell around the hematoma, reduce release of NO and TNF-α, thereby it can protect neurons.
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