Effects of environmental enrichment on sensitivity to cocaine in female rats: importance of control rates of behavior.
Effects of environmental enrichment on sensitivity to cocaine in female rats: importance of control rates of behavior.
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DOI：
10.1097/fbp.0b013e32832ec568
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发表时间：
2009-07
影响因子：
1.6
通讯作者：
Schmidt KT
中科院分区：
文献类型：
--
作者：
Smith MA;Iordanou JC;Cohen MB;Cole KT;Gergans SR;Lyle MA;Schmidt KT
丰富的环境产生中脑边缘多巴胺传递的功能变化，并改变对精神兴奋剂的敏感性。这些操作也改变了许多对兴奋剂管理敏感的行为的控制率，这可能会使隔离和丰富的受试者之间的药物效果比较困难。本研究的目的是研究环境富集对行为控制率和可卡因敏感性的影响，在自发活动，药物自我管理，条件性位置偏爱和毒性测试。在自发活动测试中，隔离大鼠表现出更大的活动后，管理的可卡因，但也有较高的控制率的活动。当自发活动表示为生理盐水对照值的百分比时，富集的大鼠相对于其自身对照比隔离的大鼠表现出更大的增加。在药物自我管理的过程中，孤立的大鼠有较高的断点上的一个渐进比的时间表的强化反应时，维持可卡因，然而，孤立的大鼠也有较高的断点在盐水替代试验和较高的利率不活跃的杠杆反应。当自我管理的数据表示为这些控制值的百分比，丰富的大鼠表现出更大的增加响应相对于自己的控制率比隔离大鼠。在位置偏好和毒性研究中，在对照条件下，未观察到隔离大鼠和富集大鼠之间存在差异。在这两个程序中，丰富的大鼠比孤立的大鼠更敏感的所有剂量的可卡因测试。这些数据强调了在研究环境富集和药物敏感性的研究中考虑行为控制率的重要性，并表明环境富集在一系列依赖性措施中增加了对可卡因的敏感性，无论是否考虑行为控制率的差异。
Environmental enrichment produces functional changes in mesolimbic dopamine transmission and alters sensitivity to psychomotor stimulants. These manipulations also alter the control rate of many behaviors that are sensitive to stimulant administration, which can make comparison of drug effects between isolated and enriched subjects difficult. The purpose of this study was to examine the effects of environmental enrichment on control rates of behavior and on sensitivity to cocaine in tests of locomotor activity, drug self-administration, conditioned place preference, and toxicity. In the locomotor activity test, isolated rats exhibited greater activity after the administration of cocaine, but also had higher control rates of activity. When locomotor activity was expressed as a percentage of saline control values, enriched rats exhibited a greater increase relative to their own control than isolated rats. In the drug self-administration procedure, isolated rats had higher breakpoints on a progressive-ratio schedule of reinforcement when responding was maintained by cocaine; however, isolated rats also had higher breakpoints in saline substitution tests and higher rates of inactive lever responding. When the self-administration data were expressed as a percentage of these control values, enriched rats exhibited a greater increase in responding relative to their own control rates than isolated rats. No differences were observed between isolated and enriched rats under control conditions in the place preference and toxicity studies. In both of these procedures, enriched rats were more sensitive than isolated rats to all the doses of cocaine tested. These data emphasize the importance of considering control rates of behavior in studies examining environmental enrichment and drug sensitivity, and suggest that environmental enrichment increases sensitivity to cocaine across a range of dependent measures whether differences in control rates of behavior are taken into account.