论文部分内容阅读
目的 :研究地塞米松对放射性大鼠脑损伤的影响。方法 :SD大鼠 2 0只 ,雌雄各半 ,体质量 (2 5 0± 5 0 ) g,随机分成 4组 ,每组 5只。未接受照射和地塞米松治疗的正常对照组、接受照射但未接受地塞米松治疗的实验对照组均进行生理盐水肌注 ,注射量与地塞米松剂量相等。另外 2组接受照射 +1或 5 m g/ kg地塞米松治疗。自照射前 3d开始肌注地塞米松或生理盐水 ,直至照射后 2周。10 Me V X射线 30 Gy照射大鼠全脑 ,14 d后取大鼠脑组织观察病理改变。颈总动脉取血 ,梯度离心 ,取中性粒细胞层 ,Northern杂交分析测定血液中性粒细胞 CD18m RNA表达水平 ,流式细胞术测定膜蛋白数量。结果 :大鼠脑组织接受照射后 ,光镜下出现明显的细胞损伤改变 ,血液中性粒细胞 CD18m RNA表达水平和膜蛋白数量在照射后较未照射组均有明显提高 (P<0 .0 1)。在照射前后 ,2个地塞米松治疗组脑细胞的损伤程度减轻 ,1mg/ kg地塞米松治疗组 CD18的表达明显受抑制 (P<0 .0 5 ) ,5 mg/ kg地塞米松治疗组的抑制作用更加明显 (P<0 .0 1)。 结论 :地塞米松可通过抑制 CD18表达的方式减轻放射性脑水肿
Objective: To study the effect of dexamethasone on brain injury in radiation-induced rats. Methods: Twenty SD rats were randomly divided into 4 groups with 5 mice in each group. The body weight was (250 ± 5 0) g. The normal control group received no radiation and dexamethasone treatment, and the experimental control group received radiation but did not receive dexamethasone treatment were normal saline intramuscular injection, injection and dexamethasone dose equal. The other two groups received irradiation at either +1 or 5 m g / kg dexamethasone. Dexamethasone or saline was intramuscularly administered 3 days before irradiation until 2 weeks after irradiation. Whole brain was irradiated with 10 Me V X-ray at 30 Gy, and after 14 days, pathological changes were observed in rat brain. The blood samples were collected from the common carotid artery and centrifuged by gradient centrifugation. The expression of CD18mRNA in neutrophils was detected by Northern hybridization and the number of membrane proteins was determined by flow cytometry. Results: After irradiation, the rat brain tissue showed obvious cell damage changes under light microscope. The expression level of CD18mRNA and the number of membrane protein in blood neutrophils were significantly increased after irradiation (P <0. 0 1). In the two dexamethasone treatment groups, the damage of brain cells was alleviated before and after irradiation. The expression of CD18 in 1 mg / kg dexamethasone group was significantly inhibited (P <0.05), and 5 mg / kg dexamethasone treatment group The inhibitory effect was more obvious (P <0.01). Conclusion: Dexamethasone can reduce radiation-induced brain edema by inhibiting the expression of CD18