淫羊藿苷对气管切开模型大鼠早期β-防御素-2和T细胞亚群的影响

目的： 探讨淫羊藿苷(icariin，ICA)对气管切开模型大鼠早期免疫相关指标的影响。方法： 将54 只SPF 级雄性SD大鼠随机分成正常对照组(A组)、模型组(B组)、模型+ICA治疗组(C组)，每组18 只。B，C组制备大鼠气 管切开模型。模型成功6 h 后给予C组ICA干预，A，B组给予等量生理盐水。分别在第24，72，168 h 取肺组织、肺 泡灌洗液及外周血。用RT-PCR检测大鼠肺组织中β-防御素-2 mRNA表达，ELISA检测肺泡灌洗液及外周血血清中β- 防御素-2 含量，流式细胞仪检测外周血T细胞亚群(CD3+，CD4+，CD8+)含量，并计算CD4+/CD8+值。结果： 气管切 开后B组大鼠肺组织β-防御素-2 mRNA及肺泡灌洗液β-防御素-2 含量在24 h 明显升高，随后逐渐降低，至168 h 降低 最明显(均P<0.05)；外周血血清β-防御素-2 含量逐渐降低，168 h 明显低于24 h(P<0.05)，但3 个时间点与A组比较差 异均无统计学意义(均P>0.05)；外周血CD3+ T细胞水平24 h 明显低于A组(P<0.05)，CD4+和CD8+ T细胞水平3 个时 间点与A组比较差异均无统计学意义，且各组组内差异亦均无统计学意义(均P>0.05)。C组ICA干预后：肺组织、肺 泡灌洗液、外周血血清β-防御素-2 含量及外周血中CD3+和CD4+ T细胞水平均逐渐升高，明显高于B组(均P<0.05)； CD8+在24 h 明显低于A组(P<0.05)，其余时间点3 组组间组内比较差异均无统计学意义(均P>0.05)；CD4+/CD8+值在 168 h 明显高于A，B组(均P<0.01)。结论： ICA 可以改善气管切开模型大鼠早期肺部免疫功能，这可能与上调肺组 织β-防御素-2 mRNA表达及肺泡灌洗液、外周血血清中β-防御素-2 含量，提高外周血中CD3+和CD4+ T细胞水平和 CD4+/CD8+值，降低CD8+ T细胞水平有关。

The negative effect of 4-methylhistamine, an H2 receptor agonist, on cytotoxicity of Ara-C for HL-60 leukemia cells

Objective: To investigate the effect of icariin (ICA) on early β-defensin-2 and T cell subsets in rats after tracheotomy. Methods: A total of 54 SPF male Sprague-Dawley rats were randomly divided into a normal control group (group A), a model group (group B), and a model+ICA treatment group (group C), with 18 rats in each group. A tracheotomy intubation model of the B and C group was prepared. After 6 h of surgery, ICA intervention was given to group C. Groups A and B were given the same amount of normal saline. Lung tissue, alveolar lavage fluid and peripheral blood were taken at 24 h, 72 h and 168 h, respectively. The expression of rat β-defensin-2 mRNA in lung tissue was detected by RT-PCR. The content of β-defensin-2 in alveolar lavage fluid and peripheral blood serum was detected by ELISA. The content of peripheral blood T cell subsets (CD3+ , CD4+ , CD8+ ) was detected by flow cytometry, and the ratio of CD4+/CD8+ was calculated. Results: After tracheotomy, the levels of β-defensin-2 mRNAand β-defensin-2 in lung tissue from the group B were increased significantly at 24 h, then they were decreased gradually, and decreased most significantly at 168 h (P<0.05). The content of β-defensin-2 in peripheral blood of group B decreased gradually, and the content of β-defensin-2 in 168 h was significantly lower than that in 24 h (P<0.05), but there was no significant difference between group B and group A (P>0.05). The level of CD3+ T cells in peripheral blood was significantly lower than that in the group A (P<0.05), but their was no significant difference in CD4+ and CD8+ T cells compared with group A (P>0.05). After ICA intervention in group C: lung tissue, alveolar lavage fluid, peripheral blood serum β -defensin-2 content, and peripheral blood CD3+ and CD4+ T cell levels were gradually increased, significantly higher than those in the group B (P<0.05). CD8+ T cell level was significantly lower than that in the group A at 24 h (P<0.05), the CD4+/CD8+ ratio was significantly higher at 168 h than those in the group A or B (both P<0.01). Conclusion: ICA can improve the early lung immune function in rats with tracheotomy, which might be related to up-regulation of β-defensin-2 in lung tissue and alveolar lavage fluid, concomitant with increases in CD3+ and CD4+ T cells and CD4+/CD8+ ratio in peripheral blood while reduction in CD8+ cells.