右美托咪定预先给药对脂多糖诱导乳鼠原代小胶质细胞炎性介质释放的影响

Effect of pretreatment on lipopolysaccharide-induced release of inflammatory mediators in primary microglias in neonatal rats

目的评价右美托咪定预先给药对脂多糖诱导乳鼠原代小胶质细胞炎性介质释放的影响。方法培养乳鼠原代小胶质细胞，采用随机数字表法，将其分为3组：对照组（c组）、脂多糖组（L组）和右美托咪定预先给药组（D组），每组10孔。C组去血清细胞培养液培养，L组加入脂多糖（终浓度1μg／m1），D组加入右美托咪定（终浓度1ng／m1），1h后加入脂多糖（终浓度1／lg／m1）。作用24h后采用Griess法测定培养上清液一氧化氮（NO）浓度，采用酶联免疫吸附法测定培养上清液前列腺素E2（PGE2）、IL-1β和TNF—α浓度，采用RT—PCR法测定细胞诱导型一氧化氮合酶（iNOS）mRNA的表达。结果与C组比较，L组和D组细胞iNOSmRNA表达上调，上清液NO、PGE2、IL-1β和TNF-α浓度升高（P〈0．01）；与L组比较，D组上述指标差异无统计学意义（P〉0．05）。结论右美托咪定预先给药对脂多糖诱导乳鼠原代小胶质细胞炎性介质释放无明显影响。

Objective To evaluate the effect of dexmedetomidine pretreatment on lipopolysaccharide （LPS）-induced release of inflammatory mediators in primary microglias in neonatal rats. Methods Purified prima- ry microglias were seeded in the plate and randomly divided into 3 groups with 10 holes in each group： control group （group C）, LPS group （group L） and dexmedetomidine pretreatment group （group D）. In group C, the cells were incubated in serum-free DMEM for 24 h. In group LPS, the cells were incubated with LPS （final con- centration 1 μg/ml） for 24 h. In group D, the ceils were pretreated with dexmedetomidine （final concentration 1 ng/ml） for 1 h, then LPS （final concentration 1μg/ml） was added and the cells were incubated for 24 h. The lev- els of nitric oxide （NO） （by Greiss method） and prostaglandin E2（PGE2）, IL-1β and TNF-α （by ELISA） in the supematant were measured after 24 h of incubation. The expression of inducible nitric oxide synthase （iNOS） mR- NA in the cells was determined by RT-PCR.Results Compared with group C, the levels of NO, PGE2, IL-1β and TNF-α, and expression of iNOS mRNA were significantly increased in groups L and D （ P 〈 0.05）. There was no significant difference in the indexes mentioned above between groups D and L （ P 〉 0.05 ）. Conclusion Pre- treatment with dexmedetomidine has no significant effect on LPS-induced release of inflammatory mediators in pri- mary microglias in neonatal rats.