地塞米松对新生猪缺氧缺血性脑损伤时谷氨酸受体的影响

为探讨地塞米松对新生儿缺氧缺血性脑病（ＨＩＥ）时谷氨酸受体（ＧｌｕＲ）的影响，作者检测了新生猪ＨＩＥ时前脑皮层粗制突触膜上ＧｌｕＲ的变化，并在建立ＨＩＥ模型前后分别使用不同剂量地塞米松，观察其对ＧｌｕＲ的影响。结果：建立ＨＩＥ模型前使用地塞米松（１０ｍｇ／ｋｇ）组，其３Ｈ－Ｇｌｕ的结合位点数显著低于ＨＩＥ模型组及其余各用药组（Ｐ＜０．０５），但各组间ＧｌｕＲ的亲和力无显著性差异。表明预防性大剂量使用地塞米松（１０ｍｇ／ｋｇ）能减少３Ｈ－Ｇｌｕ与其受体结合，对ＨＩＥ可能具有保护作用。

Dexamethasone''''s Effect on Glutamate Receptor in Experimental Hypoxic Ischemic Cerebral Injury

In order to probe into dexamethasone's effect on glutamate receptor (Glu R) in hypoxic ischemic encephalopathy (HIE) of newborn, we established newborn pigs' model of HIE to investigate Glu R in their forebrain crude synaptic membrane and the effect of dexamethasone in different HIE times and different dosages on the changes of Glu R. This study included five groups: HIE group (no medication); dexamethasone treatment group (10mg/kg before HIE); dexamethasone treatment group (10mg/kg after HIE); dexamethasone treatment group (5 mg/kg before HIE); dexamethasone treatment group (5 mg/kg after HIE). The results showed that the mean receptor density (B max ) of dexamethasone treatment group (10mg/kg before HIE) was significantly lower than that of the other groups ( P <0.05), but there was no statistic difference in the affinity of Glu R between all the experimental groups. These findings suggested that the preventive use of dexamethasone in large dosage would reduce the binding of Glu, and could possibly protect the brain tissues from damage in HIE.