CB1 and DA Receptor Deletion by RNAi in Cocaine Self-Administration

描述(申请人提供)：本K01导师研究职业发展奖是为了培训Caroline E.Bass，系初级教员。在维克森林大学的生理学和药理学，开发一个独立的假设驱动的研究项目，以调查中皮质边缘系统中受多巴胺和大麻素受体调节的成瘾过程。巴斯博士将运用她的技术开发用于传递RNA干扰(RNAi)转基因的腺相关病毒(AAV)载体，以开发她自己的项目，重点是在战略定义的大脑基因座上击倒D1、D2和CB1受体，这对可卡因增强疗效的影响，以及在药物滥用的可卡因自我给药模型中，Cananbiniod和多巴胺系统如何相互作用。巴斯博士在大麻类药物和基因表达变化方面的指导将来自艾琳·C·豪利特博士，她在行为模型，特别是大鼠自我给药方面的指导将来自大卫·C·S·罗伯茨博士，他们都是这两个领域的杰出科学家。其他辅导将涵盖与学术晋升和国家认可相称的专业技能的所有方面。为达到这一建议的目标，提出了以下具体目标：1)构建和鉴定含有导致大鼠D1、D2和CB1受体基因降解的RNAi表达盒的AAV载体，并测定这种操作引起的多巴胺和内源性大麻类神经递质分子组成的代偿性变化；2)通过将CB1RNAi-AAV注射到纹状体和延髓来研究THC的非条件性行为效应的作用部位(S)，并评估THC在诱导抗伤害、低活动、低体温和昏厥方面的效果；3)明确腹侧纹状体、背侧纹状体和VTA的D_1和D_2受体在局部特异性注射D_1或D_2 RNAi-AAV增强可卡因给药效应中的作用；4)研究去势腹侧纹状体、背侧纹状体和VTA的CB1受体对可卡因自给的影响。具体地说，CB1 RNAi-AAV将被注射到这些区域，并将评估可卡因的增强效果。在这些目标的所有阶段，将评估大麻素和多巴胺神经传递的补偿机制，以确定这些受体系统在调节可卡因摄入量方面是如何相互作用的。这些研究将解决我们在强化多巴胺受体功能方面的基本知识空白，并作为理解大麻素和多巴胺受体系统如何相互作用以调节成瘾行为的基础。这些发现可能会导致开发新的、更有效的药物成瘾治疗干预措施。

DESCRIPTION (provided by applicant): This K01 Mentored Research Career Development Award is to train Caroline E. Bass, junior faculty in the Dept. Physiology & Pharmacology at Wake Forest Univ., to develop an independent hypothesis-driven research project to investigate addiction processes that are modulated by dopamine and cannabinoid receptors in the mesocorticolimbic system. Dr. Bass will apply her skills in the development of adenoassociated virus (AAV) vectors for the delivery of RNA interference (RNAi) transgenes to develop her own project focused on the knock down of D1, D2 and CB1 receptors in strategically defined brain loci, the impact this has on the reinforcing efficacy of cocaine, and how the cananbiniod and dopamine systems interact in a cocaine self-administration model of drug abuse. Dr. Bass's mentoring in cannabinoid pharmacology and gene expression changes will come from Dr. Allyn C. Howlett, and her mentoring in the behavioral models, particularly rat self-administration, will come from Dr. David C.S. Roberts, who are distinguished scientists in these respective areas. Other mentoring will cover all aspects of professional skills commensurate with academic promotion and national recognition. The following specific aims are proposed to meet the goals of this proposal: 1) Generate and characterize AAV vectors containing RNAi expression cassettes that cause the degradation of D1, D2 and CB1 receptor mRNA in rats and determine the compensatory changes in molecular components of dopamine and endocannabinoid neurotransmission resulting from this manipulation; 2) Investigate the site(s) of action of non-conditioned behavioral effects of THC by injecting the CB1 RNAi-AAV into the striatum and medulla and assessing the efficacy of THC in inducing antinociception, hypoactivity, hypothermia, and catalepsy; 3) delineate and define the contribution of D1 and D2 receptors in the ventral striatum, dorsal striatum and VTA in the reinforcing effects of cocaine by site specific injection of D1 or D2 RNAi-AAV in rats self-administering cocaine; 4) Characterize the impact of CB1 receptor ablation from the ventral striatum, dorsal striatum and VTA on cocaine self-administration. Specifically, the CB1 RNAi-AAV will be injected into these regions and the reinforcing efficacy of cocaine will be assessed. During all stages of these aims the compensatory mechanisms in cannabinoid and dopamine neurotransmission will be assessed to determine how these receptor systems are interacting in modulating cocaine intake. These studies will address fundamental gaps in our knowledge of dopamine receptor function in reinforcement and serve as a basis for understanding how cannabinoid and dopamine receptor systems interact to regulate addictive behaviors. These findings may lead to the development of novel and more effective therapeutic interventions for drug addiction.