Conditioned place preference D1-cre. Chemogenetic inhibition during retrieval

Figure 4E.
Mice strain: D1- Cre/WT
Viruses-
AAV2-hSyn-DIO-hM4Di
Coordinates:±2.82,1,-3.69
WT;#n=7
hM4Di/CNO;#n=5
Apparatus: Each place conditioning apparatus consists of an open field enclosed in separate light- and sound-attenuating chambers. General activity and location in the open field was monitored by video recording. The floor of the open field consisted of interchangeable halves made of one of two textures. The combination of floor textures was selected on the basis of calibration studies observing that mice spend an average of about 50% time on each floor type during preference tests. Thus, the apparatus is "unbiased". Specifically, the floors are either of a rough "crushed ice" texture, coupled with walls on which appear black dots vs. a smooth floor texture coupled with walls on which appear vertical black lines. Prior to and following each session the open field and floors was cleaned using a solution of 5% virusolve.
Procedures: An unbiased conditioning procedure consists of the following phases:
Handling: 30-min sessions. Pre-conditioning bias test: a single 20 min test session is conducted during which mice are allowed to freely explore the open field with half of the arena containing the "crushed ice" floor and dots walls and half of the arena containing the "smooth" floor and straight lines walls. Conditioning: 3 days 2 session/day. Mice are randomly assigned to one of two groups, pairing cocaine (10 mg/kg IP) to either the ‘crushed ice’ or ‘smooth’ contexts, while saline conditioning (10 ml/kg) occurred on the opposite context. On all sessions, mice have access to the entire apparatus with the same floor and walls type on both sides. Post-conditioning bias test: identical to Pre-conditioning. Each CPP experiment was performed on a different group of mice, where Pre-conditioning and Post-conditioning bias test was measured within the same group of mice. For chemogenetic inhibition during conditioning, CNO (10 mg/kg, IP) was injected 30min prior to cocaine. For chemogenetic inhibition during retrieval, mice went through the regular CPP protocol, including a retrieval test, following which they were subject to another conditioning day and finally, to an additional test 30min after CNO (10 mg/Kg, IP) injection.

图4E.
小鼠品系：D1-Cre/WT
病毒-
AAV2-hSyn-DIO-hM4Di
坐标：±2.82,1,-3.69
野生型；#n=7
hM4Di/CNO；#n=5
实验装置：每个场所条件化装置由一个开放式场所以及单独的防光和隔音室组成。开放式场中的总体活动及位置通过视频记录进行监测。开放式场的地板由可互换的两部分组成，其材质为两种纹理中的一种。地板纹理的组合基于校准研究的结果，研究表明在偏好测试中，小鼠平均花费约50%的时间在每种地板类型上。因此，该装置是‘无偏见的’。具体而言，地板可以是粗糙的‘压碎冰’纹理，墙壁上出现黑点；或者平滑的地板纹理，墙壁上出现垂直的黑线。在每次实验前后，开放式场和地板均使用5%病毒溶解液进行清洁。
程序：一个无偏见的条件化程序包括以下阶段：
处理：30分钟会话。预条件化偏差测试：进行一次20分钟的测试会话，在此期间，小鼠被允许在包含‘压碎冰’地板和带点墙壁以及包含‘平滑’地板和直线墙壁的场地一半内自由探索。条件化：3天，每天2次会话。小鼠被随机分配到两组之一，将可卡因（10 mg/kg IP）与‘压碎冰’或‘平滑’情境配对，而盐水条件化（10 ml/kg）则发生在相反的情境中。在所有会话中，小鼠可以访问整个装置，两侧均具有相同的地板和墙壁类型。后条件化偏差测试：与预条件化偏差测试相同。每个条件性位置偏好（CPP）实验都是在不同的小鼠群体中进行的，其中预条件化和后条件化偏差测试是在同一组小鼠中进行测量的。在条件化过程中的化学遗传抑制中，CNO（10 mg/kg，IP）在可卡因注射前30分钟注入。在回忆过程中的化学遗传抑制中，小鼠遵循常规CPP协议，包括回忆测试，之后进行另一个条件化日，最后在CNO（10 mg/Kg，IP）注射后30分钟进行额外的测试。