Telemetric monitoring of blood pressure in freely moving mice: a preliminary study

Abstract

This paper describes for the first time the possibility for recording the systolic pressure (SP), diastolic pressure (DP), and the mean arterial pressure (MAP) as well as the heart rate (HR) and locomotor activity (LA) in freely moving mice, using a commercially available telemetry and data acquisition system. The system comprises a new, small radio-telemetry transmitter implanted in the peritoneal cavity, a receiver board placed underneath the home cage, a multiplexer and a computer-based data acquisition system. The signals from the receiver were consolidated by the multiplexer and were stored and analysed by the computer. The telemetered pressure signals (absolute pressure) were corrected automatically for changes in atmospheric pressure measured by an ambient pressure monitor. The effects of implantation on animal behaviour, and, after the animals had recovered, the effects of handling on the SP, DP, MAP and HR were examined. The radio-telemetry system for recording the SP, DP, MAP and HR provides an accurate and reliable method for monitoring the direct effects of handling on SP, DP, MAP and HR. In addition, by using this new blood pressure (BP) transmitter, we maintain that BP measurements in freely moving mice are more efficient, reliable, and less labour-intensive than the measurement techniques described in the literature thus far.

Doppler Estimation of Reduced Coronary Flow Reserve in Mice with Pressure Overload Cardiac Hypertrophy

“…Isoflurane is known to slightly decrease peripheral vascular resistance, heart rate, and blood pressure such that these parameters may be slightly reduced at baseline. The baseline heart rates (393 to 446 b/min) at 1% isoflurane are similar to those recorded by telemetry from sleeping or resting mice (Kramer et al, 1999). The coronary vasodilator effects of isoflurane have been known for many years (Crystal et al, 1995;Crystal, 1996;Gamperi et al, 2002), but Kober et al (2005) was the first to propose isoflurane as a noninvasive coronary vasodilator for estimating CFR in mice.…”

Autonomic control of blood pressure in mice: basic physiology and effects of genetic modification

“…Mouse ECG changes in response to myocardial ischemia are comparable to those observed in rats, showing R wave enlargement and ST-segment elevation (219). Until recently, the view (17,18,60,88,108,112,129,131,132,138,139,183) References are given for mouse data only. For human data, a normal range is indicated.…”

“…So far, only a few reports have been published (17,18,60,108,129,138,139,183). After the implantation of the pressure sensor, blood pressure and heart rates (HRs) are slightly elevated for 4-5 days (17).…”

Importance of Circadian Rhythms for Regulation of the Cardiovascular System - Studies in Animal and Man

“…The availability of implantable radiotelemetric devices made it possible to study various cardiovascular functions in freely-moving, unrestrained animals [2][3][4][5]. There is a clear-cut advantage of radiotelemetry over the conventional tail-cuff method since radiotelemetry does not induce stress reactions in experimental animals.…”