【作者】 贾玉芳；

【导师】 钱志红；

【作者基本信息】 苏州大学 ， 妇产科学， 2011， 硕士

【摘要】 目的:通过给妊娠第19天SD孕鼠腹腔注射细菌脂多糖,观察褪黑素对急性分离胎鼠脑细胞内游离钙的影响,探讨褪黑素对脑损伤的保护作用。方法:72只SD孕鼠随机分为:LPS处理组(LPS组)、MT处理组(MT组)、空白对照组,每组24只孕鼠。LPS组和空白对照组分别予腹腔注射LPS(500μg/kg)和等容积生理盐水;MT组孕鼠同时腹腔注射LPS 500μg/kg +MT 10mg/kg。分别于给药后1h、6h、12h、24h、48h、72h剖腹取出胎鼠,急性分离脑组织,新型荧光探针Fluo-3/AM负载胎鼠脑细胞,流式细胞术检测胎鼠细胞内游离钙的平均荧光强度。结果:1、LPS组各小组随着注药后观察时间的延长,脑细胞钙离子荧光值于6h开始明显上升,12h达到高峰,各时间点均明显高于对照组(P<0.001),具有统计学差异。且1h与6h、6h与12h、12h与24h、24h与48h,P均<0.05,均有统计学意义;48h与72h比较,P >0.05,无统计学差异,但仍呈上升趋势。2、MT组72h与LPS组72h组比较P>0.05,无统计学意义,但其值低于LPS组,6h、12h分别与LPS组比较P <0.001,其余各时间点钙离子荧光值均低于LPS组(P <0.05),差异有统计学意义。结论:1、脂多糖通过诱导胎鼠脑细胞内钙离子超载,导致脑损伤。2、细胞内钙超载是胎鼠脑细胞损伤机制的一个重要环节。3、褪黑素通过抑制细胞内钙超载,对脂多糖诱导的胎鼠脑细胞损伤有保护作用。随着对新生儿缺血缺氧性脑病(HIE)发病机制研究的不断深入,这将为HIE脑损伤的保护治疗提供新的策略与方法。更多还原

【Abstract】 Objective : To observe the effects of intracellular calcium in the brain cells of acutely isolated fetal mouse and investigate the protection of melatonin on brain injury, by injecting lipopolysaccharide in the abdomen of SD pregnant rats of 19 days of pregnancy.Methods: The 72 pregnant Sprague-Dawley rats of 19 days of pregnancy were divided randomly into three groups:the intrauterine infection group (LPS group), the melatonin group (MT group) and the blank control group, 24 in each group. In LPS group, the pregnant rats received an intraperitoneal (i.p.) injection of LPS (500μg/kg). the control group injected with saline intraperitoneally. In MT group, the rats were treated with LPS 500μg/kg and MT 10 mg/kg simultaneously. Then, the fetuses were removed by laparotomy, according to the time after injection, respectively: 1h、6h、12h、24h、48h、72h, and the brain tissues were isolated acutely. Novel fluorescent probe Fluo-3/AM loaded fetal rat brain cells. The average fluorescence intensity of intracellular calcium of fetal rats was detected by flow cytometry.Results:1. With the observation time of injected LPS group, the calcium fluorescence values of brain cells are significantly increased at 6h and peaked at 12h, were significantly higher (P<0.001)at different time points. And 1h and 6h compared, 6h and 12h compared, 12h and 24h compared, 24h and 48h compared, all P<0.05; 48h and 72h compared, P>0.05, but still on an upward trend.2. The value of calcium fluorescence in the MT group at 72h is lower than the LPS group at 72h, but is not statistically significant (P>0.05), The value of calcium fluorescence in the MT group at 6h and 12h is significantly lower than the LPS group (P<0.001), the calcium fluorescence of other groups at each time point were significantly lower than LPS group (P<0.05). Conclusions:1. LPS result in brain damage by inducing intracellular calcium overload in brain cells of fetal rat.2. Intracellular calcium overload is an important part of the mechanism of brain cell injury of fetal rat.3. Melatonin has a protective effect on lipopolysaccharide-induced brain cells injury of fetal rat by inhibiting intracellular calcium overload. With the deepening of the study on the pathogenesis of HIE, which will provide a new treatment strategies and methods for the protection of brain injury in HIE.更多还原