The effect of dexamethasone with different concentrations and different stimulating periods on the expression of glucocorticoid receptors （GRα, GRβ） protein was investigated in human monocyte cell line THP-1. The cultured human monocyte line THP-1 cells were stimulated by dexamethasone with different concentrations and different periods. The expression of GRα and GRβ protein was detected by Western hlotting. The results showed that the expression of GRα and GRβ was detected in the THP-1 cells, The quantity of GRα expression was reduced by dexamethasone under the same concentration with the prolongation of expression was increased by dexamethasone treatment the stimulating periods. The quantity of GRβ in a time- and dose-dependent manner. It was concluded that dexamethasone stimulation time-dependently reduced the GRα expression in THP-1 cells. Dexamethasone stimulation time- and dose-dependently increased the GRβ expression in THP- 1 cells. The expression of GRα and GRβas regulated by glucocorticoid.
目的探讨β受体阻滞剂(普奈洛尔)对大鼠脑创伤后脑组织中白细胞介素-1β(IL-1β)和白细胞介素-1受体拮抗剂(IL-1Ra)的影响。方法选取SD大鼠72只,随机分为对照组(36只)、治疗组(36只)。采用改良的Feeney法致大鼠右顶叶脑创伤模型,分别给予生理盐水、普奈洛尔腹腔注射(40mg/kg)。每组于致伤后6、24、72小时3个时相点,取右顶叶损伤区脑组织,苏木精-伊红染色(HE染色)法观察其病理变化,免疫组织化学和免疫印迹(W estern b lotting)方法检测其中IL-1β和IL-1Ra的表达。结果对照组:伤后6小时即可见变性坏死神经元,且IL-1β有大量表达,24小时达高峰;IL-1Ra有极少表达并逐渐升高。治疗组:变性坏死神经元明显减少,IL-1β表达降低;而IL-1Ra 6小时即有明显表达并持续至72小时;且IL-1β/IL-1Ra比值较对照组降低。两组比较,差异具有统计学意义(P<0.05)。结论β受体阻滞剂能明显降低大鼠脑损伤区IL-1β表达、提高IL-1Ra表达,可能对减轻大鼠脑创伤后炎性损伤具有一定作用。
Human monoeyte leukemia cell line THP-1 was stimulated with lipopolysaccharide （LPS） to simulate the sepsis model and the expression of human glucocorticoid receptor-α （GR-α） mRNA in montocytes with endotoxin tolerance was investigated. THP-1 cells were cultured in serum-free medium, randomly divided into groups A, B, C, D and E, and stimulated with 0, 10, 10, 100, 0 ng/mL LPS for 24 h followed with 100, 100, 10, 100, 0 ng/mL LPS for another 24 h respectively. The expression of GR-α mRNA was detected by semi-quantitative reverse transcriptional polymerase chain reaction. Tumor necrosis factor-α （TNF-α） was determined by enzyme linked immunosorbent assay （ELISA）. The results showed that the A values of GR-α/β-actin in groups A, B, C, D and E was 0. 607±0. 006, 0. 368±0. 005, 0. 484±0. 008, 0. 509±0. 004 and 0. 564±0. 014 respectively with the difference being significant among the groups （P〈0. 05）. The GR-α mRNA expression was negatively correlated with the TNF-α expression （P〈0. 01）. It was concluded that the down-regulation of the expression of GR-α mRNA in endotoxin tolerance THP-1 cells might play an important role in the development of endotoxin tolerance in THP-1 cells.
