Effects of Unpredictable and Uncontrollable Aversive Stimulus upon Long-term Adaptive Behavior in Rats

在三个实验中，使用两个名为KGbox-24的盒子研究了可预测/不可预测的网格电击对大鼠长期适应行为的影响。在每个实验中，将大鼠成对运行，并以VT-6 min时间表每天24小时对一对大鼠中的两只大鼠给予短暂的不可避免的电击，持续20天。对每对大鼠中的一只，电击之前总是给予1分钟的音调，但对另一只大鼠，电击是在没有信号的情况下给予的。在此应激阶段之前是8-10天的基线阶段，在此期间不给予电击。在KGbox-24中，在12：12-h光：暗循环条件下，以1-min为单位连续测量大鼠的进食和饮水以及运动和直立。所有三个实验本质上是相同的，但在实验2和3中，准备了一个饲养笼对照组，每天中午测量无休克对照大鼠的体重。并对实验箱中大鼠的体重进行了测量。 关于我们 在实验2和3中，在KGbox-24中运行的大鼠的体重在应激阶段比在无电击的家庭笼中运行的大鼠的体重显著降低。在所有三个实验中，在实验箱中运行的大鼠中，暴露于可预测的电击的大鼠比暴露于不可预测的电击的大鼠体重减轻相对更多。可预测的冲击比不可预测的冲击压力更大，这一事实与短期实验中通常发现的相反效果形成鲜明对比。但这一事实与Abbott等人（1984）最近提出的建议是一致的，他们区分了可预测/不可预测的冲击对压力的短期影响和长期影响。其他行为的详细分析结果在其他地方介绍。可控/不可控电击对大鼠长期适应行为影响的研究原计划但因时间紧迫而未进行。少

The effects of predictable/unpredictable grid-shocks upon rats' long-term adaptive behavior were studied in three experiments using two boxes named KGbox-24. In each experiment, rats were run in a pair and brief inescapable shocks were given to both rats of a pair with a VT-6 min schedule over 24 hours a day for 20 days. To one rat of each pair, shocks were always given preceded by a 1-min tone, but to the other rat, shocks were given unsignaled. This stress phase was preceded by a baseline phase of 8-10 days, during which no shocks were given. In the KGbox-24, eating and drinking, as well as locomotion and rearing, of rats were continuously measured in 1-min units under the condition of 12:12-h light:dark cycle. All three experiments were of essentially the same nature, but in Experiments 2 and 3, a home-cage control group was prepared and the body weight of shock-free control rats was measured daily at the noon time. The body weight of rats run in the experimental boxes was also meas … More ured daily at the noon time, taking them out temporarily from the boxes.In Experiments 2 and 3, the hody weight of rats run in the KGbox-24 decreased substantially during the stress phase compared with that of those kept in the shock-free home cages. Of those run in the experimental boxes, rats exposed to the predictable shocks lost relatively more body weight than those exposed to the unpredictable shocks in all three experiments. This fact of greater stressfulness of predictable shocks over unpredictable shocks contrasts sharply with the opposite effect usually found in short-term experiments. But the fact is in line with the suggestion made recently by Abbott et al (1984) who distinguished the short-term effects and long-term effects of predictable/unpredictable shocks upon stress. The results of more detailed analyses of other behaviors are presented elsewhere.A study on the effects of controllable/uncontrollable shocks upon long-term adaptive behavior of rats had been originally planned but was not conducted because of shortage of time. Less