SURGERY/CARDIAC FUNCTION
The Center performs animal surgeries (myocardial ischemia with/without reperfusion, transverse aortic constriction, apical resection, intracardiac injection, splenic transplant, radiotelemeter implantation, et al) and measures cardiac function (echo, PV loop and electrophysiology study) for the investigators in the Center, as well as others on campus. This suite of instruments and services also provides robust educational opportunities for trainees and faculty.
VisualSonics Vevo 3100 High Resolution in vivo Imaging System The Center houses a VisualSonics Vevo 3100 High Resolution in vivo Imaging System (photo, right). This system is a non-invasive ultrasound-based method for viewing extremely small physiological structures in mice. This real-time, in vivo imaging system has a spatial resolution down to 30 microns—the highest resolution available—and provides advanced imaging modules such as 4D and strain.
Surgery Stations The Core has five surgery stations. Each station is equipped with a dissecting microscope (Olympus/Nikon); a light source and fiber optics; a mouse ventilator (Hugo Sachs) connected to supplemental oxygen; an automatic, temperature-regulated heat lamp; and a continuously heated water blanket (Braintree Science) to ensure core body temperature is maintained at 36.5–37.5°C. The ECG monitoring system (AdInstruments) or a portable heating and monitoring surgical board (Harvard) can record vital signs of the animal during surgeries.
Telemetry In addition to traditional telemetry for ECG, blood pressure, or body temperature, the Center also houses a complete 8 channel telemetry system (Data Sciences International, DSI) used to simultaneously measure electroencephalogram (EEG) and electromusculogram (EMG), and perform video monitoring for assessment of sleep/wake cycles and sleep scoring in mice. The system is equipped with 8 HD-X02 implants (two biopotentials, temperature, activity), 8 RPC-1 receivers, 4 video cameras (capable of monitoring 2 cages at a time), Ponemah v6.51, and NeuroScore automated scoring analysis software with Rodent Sleep module. In addition to automated sleep scoring, the system is also capable of seizure detection in rodent models.
Left Ventricular Catheterization System The Core is also equipped with an ADVantage Pressure Volume System (ADV 500) single-segment pressure-volume(P-V) conductance and admittance system (Transonic). This system can simultaneously and continuously measure left ventricular pressure and volume in intact small animals. It automatically calibrates the volume signal with admittance technology to eliminate the need for hypertonic saline injections and cuvette calibrations. The system is equipped with two catheters for smaller (3.5 mm) or larger (4.5 mm) mice to acquire the most accurate hemodynamic measurements. The LabScribe data acquisition software (LabScribe v3) is used to record and analyze hemodynamic data online/offline.
Electrophysiology Study System The Center has a Programmed Electrical Stimulation (PES) system for evaluating refractoriness, nodal recovery time, and inducibility of arrhythmia in the ventricular and atrial myocardium in vivo or ex vivo. The system consists of an STG-3008 combined stimulator and amplifier (MultiChannel Systems) and Powerlab matrix with ML136 Animal Bio Amp operated with LabChart Pro 8.0 software (ADInstruments). The STG-3008 is connected to a 1.1-French 8-electrode octopolar catheter either alone (EPR-800, Millar) or bearing a lumen for drug or test agent delivery (EPR-801, Millar). The octopolar catheter facilitates programmed region-specific stimulation of cardiac tissue and concurrent monitoring of intracardiac electrophysiology across the different chambers of the beating heart.