Department of Biomedical Engineering, National Cheng Kung University, Tainan, Taiwan, Republic of China.
J Neural Eng. 2013 Aug;10(4):046007. doi: 10.1088/1741-2560/10/4/046007. Epub 2013 Jun 14.
Fast-scan cyclic voltammetry (FSCV) is commonly used to monitor phasic dopamine release, which is usually performed using tethered recording and for limited types of animal behavior. It is necessary to design a wireless dopamine sensing system for animal behavior experiments.
This study integrates a wireless FSCV system for monitoring the dopamine signal in the ventral striatum with an electrical stimulator that induces biphasic current to excite dopaminergic neurons in awake freely moving rats. The measured dopamine signals are unidirectionally transmitted from the wireless FSCV module to the host unit. To reduce electrical artifacts, an optocoupler and a separate power are applied to isolate the FSCV system and electrical stimulator, which can be activated by an infrared controller.
In the validation test, the wireless backpack system has similar performance in comparison with a conventional wired system and it does not significantly affect the locomotor activity of the rat. In the cocaine administration test, the maximum electrically elicited dopamine signals increased to around 230% of the initial value 20 min after the injection of 10 mg kg(-1) cocaine. In a classical conditioning test, the dopamine signal in response to a cue increased to around 60 nM over 50 successive trials while the electrically evoked dopamine concentration decreased from about 90 to 50 nM in the maintenance phase. In contrast, the cue-evoked dopamine concentration progressively decreased and the electrically evoked dopamine was eliminated during the extinction phase. In the histological evaluation, there was little damage to brain tissue after five months chronic implantation of the stimulating electrode.
We have developed an integrated wireless voltammetry system for measuring dopamine concentration and providing electrical stimulation. The developed wireless FSCV system is proven to be a useful experimental tool for the continuous monitoring of dopamine levels during animal learning behavior studies of freely moving rats.
快速扫描循环伏安法（FSCV）常用于监测阶段性多巴胺释放，通常使用系绳记录并针对有限类型的动物行为进行。有必要为动物行为实验设计一种无线多巴胺感应系统。
本研究整合了一种无线 FSCV 系统，用于监测腹侧纹状体中的多巴胺信号，以及一个电刺激器，该刺激器可诱导双相电流以刺激清醒自由活动大鼠中的多巴胺能神经元。所测量的多巴胺信号从无线 FSCV 模块单向传输到主机单元。为了减少电伪影，应用了光电耦合器和单独的电源来隔离 FSCV 系统和电刺激器，它们可以由红外控制器激活。
在验证测试中，无线背包系统的性能与传统的有线系统相似，且不会显著影响大鼠的运动活动。在可卡因给药测试中，注射 10mg/kg 可卡因 20 分钟后，电激发的多巴胺信号最大增加到初始值的 230%左右。在经典条件反射测试中，响应提示的多巴胺信号在 50 次连续试验中增加到约 60nm，而在维持阶段，电激发的多巴胺浓度从约 90nm 降低到 50nm。相比之下，在消退阶段，提示引发的多巴胺浓度逐渐降低，电激发的多巴胺被消除。在组织学评估中，在对刺激电极进行五个月的慢性植入后，脑组织几乎没有损伤。
我们已经开发出一种用于测量多巴胺浓度并提供电刺激的集成无线伏安法系统。所开发的无线 FSCV 系统已被证明是一种有用的实验工具，可用于在自由活动大鼠的动物学习行为研究中连续监测多巴胺水平。
