Continuous Arterial Pressure Monitoring in Conscious Rodents Using Implantable Telemetry and Comparison with the Tail-Cuff Method

Summary

This protocol details the application of implantable telemetry for continuous and reliable arterial pressure monitoring in conscious rodents, covering surgical implantation, postoperative care, data acquisition, and comparison with the tail-cuff method.

Abstract

Radio telemetry enables reliable, continuous arterial blood pressure (BP) monitoring in conscious rodents under physiological conditions, while minimizing operator-related artifacts. The implantable transmitter includes a pressure-sensing catheter, and the implantation procedure varies depending on the species used and the purpose of the study. In rodents, the most common approaches are implantation through the carotid artery or the abdominal aorta. The carotid artery approach is often favored for its direct path to the aortic arch, facilitating accurate central pressure measurement, while the abdominal aorta approach is also widely utilized for chronic studies. Compared with non-invasive methods such as tail-cuff, implantable telemetry provides more accurate and consistent measurements, making it especially useful for hypertension studies that require precise long-term BP monitoring. This protocol details anesthesia, surgical implantation techniques, and postoperative care, as well as procedures for acquiring and analyzing hemodynamic parameters-systolic, diastolic, and mean arterial pressure and heart rate (HR)-together with a comparative evaluation against tail-cuff measurements.

Introduction

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 measurement^1,2,3. 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 variations^4,5. These issues compromise accuracy and reproducibility, restricting their use in long-term hemody....

Protocol

All experimental procedures were approved by the Institutional Animal Care and Use Committee (IACUC) of Xi'an Jiaotong University (No. XJTUAE2025-2784) and were conducted in accordance with institutional and national guidelines for the care and use of laboratory animals. Eight-week-old male spontaneously hypertensive rats (SHRs) and C57BL/6 mice were used in the experiments.

1. Animal preparation

1. Housing conditions: House all animals in environmentally controlled rooms. Maintain an ambient temperature of 21 °C and a relative humidity of 60%. Set a 12 h light/12 h dark cycle. Provide standard laboratory ....

Results

Continuous telemetric recording of BP and HR in C57BL/6 Mice
Eight-week-old male C57BL/6 mice were randomized to undergo transmitter implantation by carotid artery cannulation (CAC) or abdominal aorta cannulation (AAC). After 10 days of recovery, baseline BP was recorded. Continuous 24 h monitoring confirmed stable and reliable signals with the expected circadian rhythm, showing slightly higher nocturnal than diurnal values. Compared with CAC, AAC resulted in higher SBP (Figure 8.......

Discussion

Critical steps within the protocol
Implantable telemetry is widely recognized as the gold standard for continuous, high-fidelity cardiovascular monitoring in conscious, freely moving rodents^31,32. A critical step is the selection of the catheter implantation site, either the carotid artery or the abdominal aorta, based on experimental goals. Carotid artery implantation offers technical simplicity and allows catheter advancement into the asc.......

Materials

List of materials used in this article

Name	Company	Catalog Number	Comments
APR-1 Ambient Pressure Reference	Data Sciences International (DSI)		The APR-1 Ambient Pressure Reference is a required component of each DSI telemetry system where pressure measurements are being monitored in order to dynamically compensate for the effects change in barometric pressure has on the absolute (relative to vacuum) measurements taken by the telemetry implants
Cellulose patch kit	Data Sciences International (DSI)	370-0036-001
Glutaraldehyde	MetriCide	89132-856
Graefe Forceps-curved, with teeth	Data Sciences International (DSI)	11054-10
Implant(HD-S10)	Data Sciences International (DSI)	825969
Implant(HD-S10)	Data Sciences International (DSI)	910265
Implant(HD-X11)	Data Sciences International (DSI)	1315981
Implant(HD-X11)	Data Sciences International (DSI)	1315986
isoflurane	RWD Life Science	R510-22-10
Lexar-Baby Scissors-straight, 10 cm	Data Sciences International (DSI)	14078-10
Matrix 2.0 (MX2)	Data Sciences International (DSI)		The Matrix 2.0 (MX2) manages communication between PhysioTel and PhysioTel HD telemetry implants and the acquisition computer.
Moria Instrument Case	Data Sciences International (DSI)	20311-21
Normal Saline	Kelong Pharmaceutical	C1250213B1
Olsen-Hegar Needle Holder-extra delicate	Data Sciences International (DSI)	12002-12
pentobarbital sodium	Sigma-Aldrich	P3761
RPC-1 receivers	Data Sciences International (DSI)	34668	The RPC-1 receiver is most often used for monitoring animals housed in plastic cages that can be placed on top of the receiver. The RPC-1 receiver provides reliable reception of data transmitted via digital telemetry and has two receiving antennae oriented at right angles to minimize dropouts due to directionality of the transmission pattern.
RPC-1 receivers	Data Sciences International (DSI)	34669
Tergazyme	Sigma-Aldrich	Z273287
Vessel Cannulation Forceps, 11 cm long	Data Sciences International (DSI)	00608-11
Vessel Dilator-45 degree angled tip, 13.5 cm long	Data Sciences International (DSI)	00276-13
Vetbond Tissue Adhesive	Minnesota Mining and Manufacturing Company (3M)	1469SB
Xylazine 20	Sigma-Aldrich	X1251
Zoletil 50	Virbac Laboratories