内毒素血症致牙髓组织病理学改变的实验研究

The experimental study of the pathological lesion of dental pulp induced by small dose of endotoxin in rabbits

目的：观察家兔病理性氧供依赖性（ｐａｔｈｏｌｏｇｉｃａｌｏｘｙｇｅｎｓｕｐｐｌｙｄｅｐｅｎｄｅｎｃｅ，ＰＯＳＤ）模型中各组织，特别是牙髓组织的病理学改变，以及抗ｒｈＴＮＦ单克隆抗体对实验动物是否有保护作用。方法：２８只大耳白兔随机分为对照、内毒素、抗体保护和无关抗体４组，每组７只。以小剂量大肠杆菌内毒素分次注射复制ＰＯＳＤ模型。ＥＬＩＳＡ测定血中ＴＮＦ浓度。采用组织学、组织化学和免疫组化法评价牙髓形态学特征。结果：①内毒素组与无关抗体组的牙髓组织有充血、水肿、渗出、弥漫性血管内凝血等病理变化，而对照组和抗体保护组形态正常；②内毒素组的ＴＮＦ浓度明显高于对照组（Ｐ＜０．０１），抗体保护组的ＴＮＦ浓度则明显低于无关抗体组（Ｐ＜０．０１）。结论：内毒素血症可致牙髓组织的病理学改变，抗ｒｈＴＮＦ单抗可以阻断其病变，具有临床应用前景。

Aim: The pathological lesion was observed in the tissues,especially in the dental pulp of the experimental model of the pathological oxygen supply dependence (POSD) in rabbits and whether anti-rhTNF McAb was effective in endotoxemia rabbits. Methods: Twenty-eight rabbits were randomly assigned to one of four groups, i. e. endotoxemia,control, anti-rhTNF McAb and non correlated antibody groups, each consisting of seven animals. The experimental model of the POSD in rabbits by i.v small dose of endotoxin from Escherichia coli, and ELISA was used to assay blood plasma TNF concentration. The morphologic changes of the pulps were evaluated by histopathologically, histochemically and immunohistochemical techniques. Results: ① The pathological lesions of congestion edema and disseminated intravascular coagulation(DIC)was presented in the dental pulps of endotoxin group and non correlated antibody group.While there were normal morphology in the pulps of control group and anti-rhTNF McAb group.②Blood plasma TNF concentration in endotoxin group at any time point was obviously higher than that in control group(P<0.01), while in anti-rhTNF McAb group,TNF concentration was significantly lower than that in non correlated antibody groups(P<0.01). Conclusions: The pathological lesion of dental pulps was induced by endotoxemia in rabbits,and anti-rhTNF McAb was effective in correcting the lesions, but the experimental results for clinical use, therc are still many problems awaiting further research.