Behavioral and Physiolosical Characteristics of the Animal Model of Mental Retardation (Fetal Alcohol Syndrome)

本研究旨在阐明产前酒精暴露对大鼠生理活动节律、被动回避学习和海马脑电图节律性活动的影响。研究对象为Wistar-Imamichi株雌性白化大鼠及其后代。实验组雌性大鼠在妊娠0 ~ 18天内以6%酒精溶液作为唯一的液体来源，处理后给予母鼠及子鼠饮水。对照组大鼠在实验期间任意饮水。出生后21 ~ 85 d，每组8只幼犬分别在LD12∶12条件下和DD条件下进行活性试验。在整个实验过程中，接触酒精的后代比对照组的后代更活跃。在LD12: 12照明提前或延迟相移6小时后，两组的所有后代都可以看到昼夜节律的重新恢复，尽管酒精暴露的后代在两次相移后都比对照大鼠更快地重新恢复。每组46只幼犬分别于出生后21日龄、46日龄、70日龄进行被动回避试验。接触酒精的后代比对照组的后代需要更多的灭绝试验。在保留测试中，两组之间在活动和情绪方面没有显著差异，尽管与对照组相比，酒精暴露组的排尿发生率迅速下降。分别记录每组10只幼鼠在行走、运动、翻身、头部运动、嗅探等自主运动和快速眼动睡眠时的海马脑电图。在对照组中，海马节律性慢活动在自主运动中表现明显，尤其是在行走、运动和跑步时，以及在快速眼动睡眠期间。酒精暴露的后代在排尿过程中表现出不清楚的节律性缓慢活动

This study aimed to elucidate the effects of prenatal alcohol exposure on circadian activity rhythms, passive avoidance learning, and rhythmic activity of hippocampal EEG in the rat. Subjects were female albino rats of the Wistar-Imamichi strain and their offspring. Female rats of experimental group were administered 6% alcohol solution ad libitum as the sole fuluid source during 0-18 days of gestation, while after these treatment, mother rats and also their offspring were provided with water. Control rats were provided with water ad libitum throuthout the experiment. Activity test was performed with 8 pups in each group under the LD12 : 12 condition and then under the DD condition during 21-85 days after birth. Alcohol-exposed offspring were more active throughout the experiment than control offspring. Re-entrainment of circadian rhythms after 6 hours advanced or delayd phase-shifts of the LD12 : 12 illumination could be seen in all offspring in both groups, though alcohol-exposed offspring re-entrained more rapidly after both phase-shifts than control rats. Passive avoidance test was performed with 46 pups in each group, during 10 days from 21, 46, 70 days of age after birth respectively. Alcohol-exposed offspring required more trials for extinction than control offspring. There were no significant differences on activity and on emotionality during retention test traials between two groups, though the incidence of urination in the alcohol-exposed group decreased quickly compared with those in the control group. Hippocampal EEG were recorded monopolarly from 10 offspring in each group during voluntary movements, such as walking, locomotion, realing, head movement and sniffing, and during REM sleep. In the control group, appearances of hippocampal rhythmic slow activity were remarkable during voluntary movements, especially during walking, locomotion and rialing, and also during REM sleep. Alcohol-exposed offspring showed unclear rhythmic slow activity during volun