大鼠孕期地塞米松给药次数对仔鼠脑星形胶质细胞发育的影响

Influences of Different Prenatal Administration Procedure of Dexamethasone(DEX) on the Development of Astrocyte in Offspring Rats

目的通过产前地塞米松治疗,探讨不同给药疗程对仔鼠脑星形胶质细胞发育的影响。方法实验孕大鼠随机分为3种情况用药,孕期1剂组于孕17d肌注地塞米松0.8mg/kg/d,孕期4剂组于孕17、18、19、20d各肌注地塞米松0.8mg/kg/d,对照组肌注等量生理盐水。对各组孕鼠所生的仔鼠,分别于生后第1、7、14d称脑重,检测大脑白质与海马胶质纤维酸性蛋白(GFAP)的表达情况,并与对照组作比较。结果孕期激素治疗各组仔鼠全脑重量较对照组下降,尤以4剂组最明显;孕期激素治疗4剂组7日龄、14日龄鼠脑海马、白质GFAP的表达较对照组减少,1剂组与对照组相比无明显差异。结论大鼠孕期重复激素治疗会影响后代脑星形胶质细胞的成熟。

Objects To explore the influence of different programs of antenatal treatment with dexamethasone （DXM） on the development of astroeyte in offspring rats and observe the relationship between dosage and effent. Methods The pregnant SD rats were divided into 3 groups randomly （one single-dose-treatment, one four-dose-treatment and one control）. Rats in single-dose-treatment group were injected IM with DXM （0.Smg/kg/day） on day 17 of gestation, while rats in four-dose-group were injected consecutively on day 17, 18, 19, and 20 of gestation. And rats in control group received equivalent volumes of isotonic saline on same time points with four-dose-group. The whole brain of offspring rats from different groups were weighted on the 1st, 7th, and 14th day after delivery respentively. Meanwhile the expression of white matter and glial fibrillary acidic protein （GFAP） in brains of offspring rats were measured. Results The whole brain weights of offspring rats from groups treated with dexamethasone, especially the four-dose-group, were lighter than those from the control group. And the expression levels of GFAP in hippocampus and white matter of 7-day-old and 14-day-old offspring rats from four-dose-group were lower than the control group, whereas the expression level of GFAP in one-dose-group had no significant differenee with the control group. Conclusion Repeated antenatal treatment on gestational rats delays Astroeyte maturation of the brain of offspring rats.