An alternative electrode implantation and tethering approach for neuromodulation of non-cranial areas in freely moving rats

Electrical stimulation and recording from non-cranial areas in freely moving rodents often require tethered devices for monitoring from a distant location. Inspired by our experience in electrode implantation for deep brain stimulation (DBS), we developed an implantation approach, which allows for performing electrical modulation of the urinary bladder. In order to prevent the wires from being damaged by rats in freely moving conditions and compromising animal welfare, we guided the wires subcutaneously toward the nape to reach a plug, which was mounted on the skull. No complications such as infection, gastrointestinal tract injury, or inflammation occurred during or after surgery. The device allowed easy plugging and unplugging throughout the bladder stimulation and behavioral testing sessions undertaken in freely moving animals. This method enables modulation of peripheral organs in combination with DBS in freely moving rodents and can encompass many procedures such as electrical stimulation and recording, drug delivery, or electromyography.