早期触摸和丰富环境刺激对新生大鼠低血糖脑损伤的影响

Effects of Neonatal Handling and Enriched Environment Stimulation on Brain Damage in Neonatal Rats Following Hypoglycemia

目的探讨早期触摸和丰富环境刺激对新生大鼠低血糖脑损伤的影响。方法将36只新生Wistar大鼠,分为正常组、低血糖干预组及低血糖非干预组,每组各12只。正常组新生大鼠正常喂养;低血糖干预组和低血糖非干预组给予禁食12h,测定禁食12h后的血糖水平。低血糖模型建立后,低血糖非干预组和正常组新生大鼠正常喂养,与母鼠分开期间不进行触摸。低血糖干预组大鼠分别给予抚摸及环境刺激各14d:早期触摸从出生24h内开始,用毛刷从头至尾轻轻摩擦;丰富环境刺激从出生第15天开始,每日放入丰富环境中1h,持续至第28天。正常组和低血糖非干预组放入无特殊刺激的标准环境中。连续处理28d。水迷宫实验观察3组大鼠学习记忆能力;监测各组出生第0、7、14、21、28天体质量;取各组新生大鼠枕叶皮质,在光镜和电镜下观察新生大鼠大脑枕叶皮质病理改变。结果正常组新生大鼠学习记忆能力、体质量增加较低血糖非干预组和干预组明显升高(Pa<0.01);低血糖干预组学习记忆能力、体质量增加较低血糖非干预组显著升高(Pa<0.01);低血糖干预组较低血糖非干预组枕叶皮质病理改变明显改善。结论早期干预对新生大鼠脑损伤有改善作用。

Objective To explore the effects of the neonatal handling and enriched environmental stimulation on brain damage in neonatal rats with hypoglycemia. Methods Thirty - six neonatal rats were randomly divided into the normal group, hypoglycemia intervention group and the hypoglycemia non - intervention group. Those rats in hypoglycemia intervention and hypoglycemia non - intervention groups were weaned for 12 h,then the blood sugar of both groups were monitored. After neonatal rat models with hyperglycemia were prepared,the rats in hypoglycemia intervention group received the neonatal handling for 14 d and then were kept in an enriched stimulation environment for another 14 d. Rats in normal group and hypoglycemia non - intervention group were fed in the routine way. Neonatal handling was done when the rats were born for 24 h. The rat was rubbed with the brush from head to tail softly. Rats in the hypoglycemia non - intervention group was not handled. The enriched environment stimulation was used after 15 d when the rats were born. Rats in the hypoglycemia intervention group was put into the enriched environment for 1 h per day until 28 d when the rats were born, and rats in the hypoglycemia non - intervention group was put into the normal environment. Then the body weight was scaled at 0 d,7 d,14 d,21 d and 28 d when the rats were born. Space learning and memory were tested with Morris carter at their third month＇s age. After that,changes of pathology was observed in their occipital cortex. Results The weight increase,the ability of space learning,memory and the number of survival pyramid neurons of occipital cortex in normal group were better than those in hypoglycemia intervention and hypoglycemia non - intervention group（ Pa 〈0.01 ）. The ability of space learning and memory in intervention group were better than those in hypoglycemia non - intervention group （ P 〈 0. 01 ）. The change of pathology in their occipital cortex in hypoglycemia intervention group was better than that in hypoglycemia non - intervention group. Conclusion The neonatal handling and the enriched environment may improve the brain damage in neonatal rats following hypoglycemia.