Persistence of Operant Responding for Food After Prior Cocaine Exposure in Fischer 344 But Not Lewis Rats.
Persistence of Operant Responding for Food After Prior Cocaine Exposure in Fischer 344 But Not Lewis Rats.
复制标题
Fischer 344 大鼠先前接触可卡因后，操作者对食物的反应持续存在，但 Lewis 大鼠则不然。
DOI：
10.1111/ajad.13152
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发表时间：
2021
期刊：
影响因子：
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通讯作者：
Kosten,ThereseA
中科院分区：
文献类型：
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作者：
Forouzan,Shadab;Nieto,StevenJ;Kosten,ThereseA
背景和目的慢性可卡因暴露在Fischer 344 （F344）和Lewis自交系大鼠中具有不同的神经效应，这可能解释了可卡因自我给药获得和维持过程中的品系依赖性差异。我们评估了先前的可卡因暴露是否会改变这些菌株在不同阶段（获取、维持、消失、自发恢复、重新启动）对食物的操作性反应。方法slewis和F344大鼠（N = 12）连续3 d注射可卡因（15 mg/kg）或生理盐水（每小时1次）。从第二天开始，连续24天，大鼠可以进入操作室，其中一个杠杆下降导致食物颗粒的传递。然后，进行了四次灭绝实验，在这些实验中，食物不再可用，但其他刺激条件保持不变。休息2天后，在4个疗程中评估自发恢复情况。然后恢复食物递送3天，以测试重新启动，随后是渐进比例会议。结果wiss大鼠比F344大鼠更快获得操作。F344大鼠的维持率低于Lewis大鼠，但自发恢复反应较高。可卡因暴露导致F344大鼠在灭绝期间的持续反应，但Lewis大鼠没有。当食物再次可用时，所有组都重新开始反应，并且在递进比例计划下完成的最终比例没有差异。讨论和结论先前的可卡因暴露导致F344大鼠在灭绝期间持续反应，这可能反映了环境条件的增强，干扰了消除反应的能力。科学意义研究结果揭示了遗传因素对复发样行为的影响。（Am J Addict 2021; 00:00-00）
Background and ObjectivesChronic cocaine exposure has differential neural effects in Fischer 344 (F344) vs Lewis inbred rats that may explain strain‐dependent differences during acquisition vs maintenance of cocaine self‐administration. We assessed whether prior cocaine exposure alters operant responding for food across various phases (acquisition, maintenance, extinction, spontaneous recovery, reinitiation) in these strains.MethodsLewis and F344 rats (N = 12) were administered three cocaine (15 mg/kg) or saline injections at hourly intervals for 3 consecutive days. Beginning the next day for 24 days, rats had access to operant chambers in which one lever depression resulted in the delivery of a food pellet. Then, four extinction sessions were conducted in which food was no longer available, but other stimulus conditions remained the same. After a 2‐day break, spontaneous recovery was assessed over four sessions. Food delivery was then restored for 3 days to test reinitiation followed by a progressive ratio session.ResultsLewis rats acquired the operant faster than F344 rats. F344 rats showed lower maintenance rates than Lewis rats but higher spontaneous recovery responding. Cocaine exposure caused persistence of responding during extinction in F344 but not Lewis rats. All groups reinitiated responding when food was available again and did not differ in final ratios completed under the progressive ratio schedule.Discussion and ConclusionsThat prior cocaine exposure led to persistence of responding in F344 rats during extinction may reflect heightened contextual conditioning that interferes with the ability to extinguish responding.Scientific SignificanceResults have implications for the genetic contribution to relapse‐like behaviors. (Am J Addict 2021;00:00–00)