Abstract

Effects of the anxiolytic diazepam and nootropics piracetam and mexidol on passive avoidance conditioning (PAC) in rats were compared in experiments using a three-compartment apparatus. The latter consisted of a central, brightly lit compartment, a noxious dark compartment in which footshock was delivered to a rat, and a safe dark compartment, where the rat was not exposed to electric shock. Footshock during the acquisition of passive avoidance response in the control animals caused an abrupt increase in the latency to escape from the central compartment during testing but did not result in preference for a safe compartment. On the basis of these data on differential effects of footshock on PAC, we suggested that learning processes, which determined the motor response delay and the safe compartment preference, had a diverse associative nature. An increase in latency is associated with the classical fear conditioning regardless of the place of electric shock exposure. In contrast to this, the safe compartment preference is associated with the formation of the memory trace about the location of the footshock exposure. The use of pharmacological substances that affect fear and memory in different ways provided additional arguments in favor of the assumption about various associative processes determining passive avoidance learning. Reduction in the level of fear using diazepam decreased the latency of motor response compared to the control value but did not affect the preference for a safe compartment. In contrast, the mnemotropic properties of piracetam and mexidol increased the preference for a safe compartment without increasing the latency. These differential pharmacological effects confirm that PAC is based on the fear conditioning, which causes an increase in the latency to escape from the central compartment, and on the memory of the location of shock exposure, which provides the preference for the safe compartment.

中文翻译：

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地西p，吡拉西坦和美西多对被动回避反应的影响

摘要

在使用三室仪器的实验中，比较了抗焦虑地西epa和促智药吡乙酰胺和美西多对大鼠被动回避条件的影响（PAC）。后者由中央明亮的隔间，有害的黑暗隔间和足部安全的黑暗隔间组成，在黑暗的隔间中，足电被传递给大鼠，在黑暗的隔间中，大鼠未受到电击。在对照动物中获得被动回避反应的过程中，足底休克导致测试期间从中央隔室逸出的潜伏期突然增加，但并未导致偏爱安全隔室。根据这些有关足震对PAC的不同影响的数据，我们建议确定运动响应延迟和安全隔室偏好的学习过程具有多种关联性。无论电击暴露的位置如何，等待时间的增加都与经典的恐惧条件有关。与此相反，安全隔室的偏好与关于脚电击暴露位置的记忆轨迹的形成有关。使用以不同方式影响恐惧和记忆的药理物质提供了更多的论据，以支持关于确定被动回避学习的各种关联过程的假设。与对照组相比，使用地西epa降低恐惧程度可降低运动反应的潜伏期，但不影响对安全隔室的偏好。相比之下，吡乙酰胺和美西多的促血性增加了对安全隔室的偏好，而不会增加潜伏期。