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

使用两个名为KGbox-24的盒子进行了三个实验，研究了可预测/不可预测的电网冲击对大鼠长期适应行为的影响。在每个实验中，大鼠成对运行，对两只大鼠进行短暂的不可避免的电击，每对大鼠的VT-6分钟程序超过24小时，持续20天。对于每对中的一只大鼠，电击总是在1分钟的音调之前进行，而对另一只大鼠，电击是无信号的。在这个应激阶段之前，有一个8-10天的基线阶段，在此期间不给予电击。在KGbox-24上，在12：12-h光：暗周期条件下，以1min为单位连续测量大鼠的进食、饮水、活动和站立。这三个实验的性质基本相同，但在实验2和实验3中，准备了一个家庭笼养的对照组，每天中午测量无休克对照组的体重。在实验箱中运行的大鼠的体重也表示…在实验2和实验3中，在应激阶段，在KGbox-24中跑步的大鼠的体重比在没有休克的家庭笼子里的大鼠显著减轻。在实验箱中跑步的大鼠中，在所有三个实验中，暴露于可预测电击下的大鼠比那些暴露在不可预测电击下的大鼠体重减轻得相对更多。可预测冲击的压力大于不可预测冲击的这一事实，与短期实验中通常发现的相反效果形成了鲜明对比。但事实与Abbott等人(1984)最近提出的建议是一致的，他们区分了可预测/不可预测冲击对压力的短期影响和长期影响。对其他行为的更详细的分析结果在其他地方展示。关于可控/不可控冲击对大鼠长期适应行为的影响的研究原本计划进行，但由于时间短缺而没有进行。较少

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