新生鼠缺氧缺血后脑髓鞘化观察及药物干预效果

Myelination changes in brains of neonatal rats after hypoxic-ischemia and effect of drug intervention

目的 了解缺氧缺血对新生大鼠脑髓鞘化的影响及1-6二磷酸果糖(FDP)、硫酸镁(MgSO_4)、苯巴比妥(PB)3种药物急性期干预治疗的作用,评价早期治疗的疗效。方法 7日龄Wistar大鼠行左侧颈总动脉结扎,吸入8％氧气2h,立即腹腔注射FDP、MgSO_4、PB及生理盐水5d,于生后28d断头、取脑、冠状切片、行Luxol fast blue染色,计算机图象分析仪测量髓鞘染色平均吸光度和面密度。结果 缺氧缺血使新生大鼠脑髓鞘生成量减少,而成熟度未发生变化,3种药物均可使髓鞘生成量增加,但其作用不完全。结论 缺氧缺血影响了新生大鼠脑的髓鞘化,3种药物急性期干预治疗对神经纤维髓鞘化程度均有改善作用,而这种作用大多是不完全的。

Objective To study the long term effect of perinatal hypoxic brain damage on myelination. and to find out an effective approach of drug intervention. Methods We set up an animal model of hypoxic-ischemia using 7-day-old Wistar rats and observed myelination in the internal capsule, fimbria hippocampi and dorsal commissural fornix hippocampi 21 days after hypoxic-ischemia in vivo (28 days after birth). We also observed the protective effect of FDP (froctose 1-6 diphosphate), MgSO4 (magnesium sulfate) and PB (phenobarbital). administered during the acute phase of hypoxic-ischemia, on future myelination. Results The number of myelination in the internal capsule, fimbria hippocampi and dorsal commissural fornix hippocampi decreased 21 days after hypoxic-sichemia, while the maturation state of myelination remained unchanged. Acute phase intervention with FDP. MgSO4 and PB helped to improve myelination. But the effect was limited. Conclusion Brain development of rats in our model was hampered in myelination. Intervention with FDP, MgSO4 and PB during acute phase can help reducing damage to future brain development. However, such protective effect is limited.