Direct and indirect methods used to study arterial blood pressure

A number of different approaches exist for assessing blood pressure in expe rimental animals. Here, we briefly consider the traditional indirect (roden t tail-cuff) and direct (saline-filled catheter) methods of blood pressure measurement before going on to describe our experience with blood pressure telemetry in rabbits, rats. and mice. Blood pressure telemetry offers the a bility to obtain a high-fidelity recording of blood pressure continuously, for relatively Long periods of time, in conscious, freely moving animals, w ithout the limitations of restraint or anaesthesia. Since some drift in tel emeter offset and sensitivity are inevitable, recalibration of the telemete r devices immediately before implantation and following explantation is ess ential to ensure and document the accuracy of the blood pressure measuremen ts. For long-term implantations, verification of the calibration can be per formed in vivo. at least in the case of large animals, such as rabbits. Tel emetry devices suitable for small animals, such as mice, are also available now which will facilitate the accurate characterization of blood pressure in transgenic animals. Telemeter implantation methods in mice are presently difficult, with relatively low success rates being reported. However valid ation of new methods, such as the insertion of the catheter tip via the car otid artery. may make the technique more widely accessible in the near futu re.;(C) 2001 Elsevier Science Inc. All rights reserved.