Accurate and continuous monitoring of arterial blood pressure (BP) in conscious rodents is essential for cardiovascular research, especially in hypertension studies where dynamic hemodynamic changes require precise measurement1,2,3. Traditional non-invasive methods, such as the tail-cuff method, are widely used but limited by intermittent sampling, stress-related artifacts, and failure to capture circadian BP variations4,5. These issues compromise accuracy and reproducibility, restricting their use in long-term hemodynamic studies6.
Radio telemetry systems offer more accurate and consistent BP measurements. It enables continuous, high-quality BP monitoring in freely moving animals, eliminating variability from operator handling and stress caused by restraint7,8,9,10. This approach is particularly useful in hypertension research, where it is important to capture the onset, magnitude, and stability of BP elevation, as well as circadian patterns11,12,13. In addition, continuous telemetry allows detection of transient fluctuations during disease progression and provides a detailed assessment of pharmacological interventions, advantages that traditional tail-cuff methods cannot offer14.
The radio telemetry system uses an implantable transmitter with a pressure-sensing catheter, which is surgically placed at anatomical sites chosen based on the species and study design. In mice, the catheter is typically inserted through the carotid artery into the aortic arch to ensure stable signals9. For certain experiments, such as long-term studies in older or heavier mice, placement in the abdominal aorta may be preferred. In rats, the abdominal aorta is the standard site for reliable long-term recordings15. These implantation strategies allow precise measurement of systolic, diastolic, and mean arterial pressures, as well as heart rate (HR), making the telemetry system a valuable tool for phenotyping hypertensive models and evaluating therapeutic interventions16.
This protocol outlines detailed procedures for anesthesia, surgical implantation (including catheter placement options), postoperative care, and data acquisition and analysis, alongside a comparative evaluation with the tail-cuff method.