Augmentation of the neurochemical effects of cocaine in the ventral striatum and medial prefrontal cortex following preexposure to amphetamine, but not nicotine: an in vivo microdialysis study.
Augmentation of the neurochemical effects of cocaine in the ventral striatum and medial prefrontal cortex following preexposure to amphetamine, but not nicotine: an in vivo microdialysis study.
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预先暴露于安非他明（而非尼古丁）后可卡因在腹侧纹状体和内侧前额叶皮质中的神经化学作用增强：一项体内微透析研究。
DOI：
10.1016/0024-3205(94)00664-4
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发表时间：
1994
期刊：
影响因子：
6.1
通讯作者：
Schenk,S
中科院分区：
文献类型：
--
作者：
Horger,BA;Valadez,A;Wellman,PJ;Schenk,S
本研究评估了每天重复接触安非他明或尼古丁后，可卡因增加腹侧纹状体 (VS) 和内侧前额叶皮质 (mPFC) 多巴胺 (DA) 突触水平的能力。体内微透析用于测定清醒、自由活动的雄性斯普拉格-道利大鼠的 DA 水平。引导插管植入后三天，受试者每天接受 9 次暴露前注射苯丙胺（1.0 毫克/千克盐重，IP）、尼古丁（0.6 毫克/千克基础重量，SC）或载体。然后插入探针并用林格氏溶液灌注过夜。一旦建立了稳定的 DA 基线水平，受试者就接受可卡因（15 mg/kg，IP）激发注射，并每 20 分钟收集一次透析液样本。注射可卡因后，预先暴露于载体的受试者表现出 VS 中 DA 水平增加了 200%，mPFC 增加了 170%。在预先暴露于苯丙胺的受试者中，这两个区域的 DA 恢复均显着增强，在 VS 和 mPFC 中观察到的基线水平分别增加了 450% 和 285%。相比之下，在任何一个大脑区域中，预先暴露于尼古丁的受试者中可卡因诱导的 DA 水平与预先暴露于媒介物的对照组没有显着差异。根据类似的暴露前程序后可卡因的运动激活和增强作用的变化来讨论数据。
This study assessed the ability of cocaine to increase synaptic levels of dopamine (DA) in the ventral striatum (VS) and medial prefrontal cortex (mPFC) following repeated daily exposure to amphetamine or nicotine.In vivomicrodialysis was used to assay DA levels in the awake freely moving male Sprague-Dawley rat. Three days following guide cannula implantation, subjects received 9 daily preexposure injections of amphetamine (1.0 mg/kg salt weight, IP), nicotine (0.6 mg/kg base weight, SC), or vehicle. Probes were then inserted and perfused with Ringer's solution overnight. Once stable baseline levels of DA were established, the subjects received a cocaine (15 mg/kg, IP) challenge injection and dialysate samples were collected every 20 minutes. Subjects preexposed to vehicle exhibited a 200% increase in DA levels in the VS and a 170% increase in the mPFC following the cocaine injection. DA recovery was significantly augmented in both regions in amphetamine-preexposed subjects with 450% and 285% increases above baseline levels observed in the VS and mPFC, respectively. In contrast, cocaine-induced DA levels in nicotine-preexposed subjects did not differ significantly from vehicle-preexposed controls in either brain region. Data are discussed in terms of alterations in the locomotor activating and reinforcing effects of cocaine following similar preexposure procedures.