Mp100

We assembled a data reading unit to implement the I2C digital communication protocol required for the output reading of the 3D gyro included in the CardioMon lead. The reading unit comprises a microcontroller board (Arduino Mega ADK 5 V/16 MHz, Arduino, Italy), three power adapters, and three Digital/Analog (D/A) converters, one for each sensitive axis of the 3D gyro (Figure 3). The analog output signals from the reading unit have been collected and analyzed using a data acquisition system for biomedical signals (MP100, Biopac System, Goleta, CA, USA).

Electroencephalograms (EEGs) were recorded in awake freely moving animals using a digital acquisition system (Biopac System, MP-100, Inc.). The signals were amplified and filtered (high pass filter 1 Hz/low pass filter 97 Hz), then digitized at a sampling rate of 256 Hz and recorded using AcqKnowledge® software version 3.2 (Biopac Students Lab PRO software). During the recording and stimulation sessions, the mice were continuously watched to detect changes in their posture and behaviour. All sessions did not exceed 3 h and were performed between 9:00 a.m. and 5:00 p.m [27 (link)]. Digital video recordings were made with a webcam (Orbit Logitech Quickcams) located inside the Faraday cage, and the animals’ behaviour was simultaneously recorded (for detailed information on surgery and procedures).

Twenty six days after 2K1C procedure or sham operation, mice were anesthetized with a combination of ketamine/xylazine (91/9.1 mg/kg, i.p.) and a catheter (0.040 mm outer × 0.025 mm inner diameters, MicroRenathane, Braintree Science, Massachusetts, USA) was inserted into the right carotid artery for the measurement of mean arterial pressure (MAP) and heart rate (HR) recordings. The free catheter end was tunneled under the skin of the back to the level of the shoulder blades. Hemodynamic measurements were performed in conscious, freely moving mice in their own cages, two days after catheter placement, as already validated as a sufficient period for complete recovery from surgery by others [33 (link)] and standardized in our laboratory [3 ,13 (link)-15 (link)]. For the MAP and HR recordings, the arterial catheter was plugged into a disposable BP transducer (Cobe Laboratories, Colorado, USA) connected to a pressure processor amplifier and data-acquisition system (MP100, Biopac Systems, California, USA). At the beginning of the experimental session, a period of approximately 30 min was allowed for stabilization of cardiovascular parameters before the measurement of basal MAP and HR values in conscious mice (Acknowledge software, Biopac Systems).

Timings at the onset and end of treadmill exercise (i.e., when the cats began to walk and when they stopped walking) were determined by using a manually and electrically marked signal or EMG signal. Similarly, timings of occlusion were marked. The marking signals, AP, and EMG were simultaneously recorded on an eight‐channel pen‐writing recorder (Recti‐8 K, GE Marquette Medical Systems, Tokyo, Japan) and stored in a computer with an analog‐to‐digital converter (MP100, BIOPAC Systems, Santa Barbara, CA, USA) at a sampling frequency of 1 kHz. HR was estimated from the AP wave. The beat‐to‐beat values of HR and systolic, mean, and diastolic AP (SAP, MAP, and DAP, respectively) were recalculated using a software program (AcqKnowledge 3.9.1, BIOPAC Systems, Santa Barbara, CA, USA).