Psychostimulant sensitization: differential changes in accumbal shell and core dopamine
Psychostimulant sensitization: differential changes in accumbal shell and core dopamine
复制标题
DOI：
10.1016/s0014-2999(99)00824-9
复制
发表时间：
2000-01-24
影响因子：
5
通讯作者：
Di Chiara, G
中科院分区：
文献类型：
--
作者：
Cadoni, C;Solinas, M;Di Chiara, G
根据组织化学和连接差异，可将核分为壳区和核心区。最近，我们报道，行为敏化吗啡与增加多巴胺的传输在尾壳核和核的核心，以及减少反应在核壳后急性吗啡挑战。我们现在已经在对安非他明和可卡因敏感的大鼠中进行了类似的研究。通过每日单次给予1 mg/kg s.c.安非他明10天或可卡因10毫克/公斤，每天两次，共14天。在最后一次注射安非他明后10-14天和最后一次注射可卡因后7-10天进行微透析。这两个时间表导致强大的行为敏感化的挑战与0.25和0.5毫克/公斤的安非他明和5和10毫克/公斤的可卡因，分别。受试者预先暴露于安非他明表现出敏感的多巴胺传输在核的核心，但不是在核的壳。预先暴露于可卡因的受试者仅对较低剂量的可卡因表现出核心多巴胺传递的敏感性。在壳中，在较低剂量的可卡因后没有观察到变化，而在较高剂量后观察到多巴胺反应显著降低。这些结果表明，行为敏化可能是由于多巴胺在壳核和核中对药物刺激反应的相互变化。(C)2000 Elsevier Science B. V.保留所有权利。
The nucleus accumbens has been subdivided into a shell and a core compartment on the basis of histochemical and connectional differences. Recently, we reported that behavioral sensitization to morphine is associated with an increased dopamine transmission in the caudate-putamen and in the nucleus accumbens core as well as a decreased response in the nucleus accumbens shell following acute morphine challenge. We have now performed a similar study in rats sensitized to amphetamine and to cocaine. Behavioral sensitization was induced by daily administration of a single dose of 1 mg/kg s.c. of amphetamine for 10 days or of 10 mg/kg i.p. of cocaine twice a day for 14 days. Microdialysis was performed 10-14 days after the last injection of amphetamine and 7-10 days after the last injection of cocaine. Both schedules resulted in robust behavioral sensitization in response to challenge with 0.25 and 0.5 mg/kg of amphetamine and to 5 and 10 mg/kg of cocaine, respectively. Subjects pre-exposed to amphetamine showed a sensitization of dopamine transmission in the nucleus accumbens core but not in the nucleus accumbens shell. Subjects pre-exposed to cocaine showed sensitization of dopamine transmission in the core only to the lower dose of cocaine. In the shell no change was observed after the lower dose of cocaine while a significant reduction of the dopamine response was observed after the higher dose. These results suggest that behavioral sensitization might result from reciprocal changes in the response of nucleus accumbens dopamine in the shell and in the core to drug challenge. (C) 2000 Elsevier Science B.V. All rights reserved.