**6. References**

192 Modern Telemetry

These advantages and disadvantages should be taken into consideration when designing

It is important to highlight that telemetry improves data quality and quantity, which can lead to a reduction in the number of animals required for each study. In toxicology and pharmacology, telemetry may also be able to identify dose-limiting effects of a compound evidenced by subtle changes in blood pressure or heart rate so that higher dosing studies are not required. However, reducing animal numbers can also increase animal suffering, and it is important to be aware of this and make sure that it does not happen. For example, as implant miniaturization has progressed, sensor functionality has increased such that individual devices may increase in size because more parameters are being measured. Larger batteries may be required, which also makes devices more bulky. These devices will be heavier and require more invasive surgery to implant them. Therefore, it is imperative to ensure that animal numbers have been reduced as far as possible by taking the better quality and quantity of data obtained using telemetry into account when designing experiments. It also important to recognize that there can be a 'trade off' between reduction and refinement, e.g. where fewer animals are used but devices are more bulky or complex. Finally, the impact on each animal should be considered, and reducing numbers at the expense of

Fig. 6. Refinement of the surgical approach and size of the implanted device.

details by Morton et al. (2003) and Hawkins et al. (2004).

or the rat telemetric device (B). Pictures are from first author's personal collection.

Radiographic pictures acquired from two different rats implanted with either the mouse (A)

New developments in telemetry research can lead to refinements in procedures and/or reductions in animal numbers so it is essential to ensure that progress is monitored and techniques and equipment are updated whenever possible. Some ways to keep updated are using the World Wide Web and attending telemetry user group meetings. It is, however, important to use information from the web or user groups very critically, as it may not be properly refereed or refereed at all. Uncritical use could lead to welfare problems or undermine scientific validity. Further information on refinement husbandry and telemetry procedures for measuring blood pressure in laboratory animals have been described in

Here we have reviewed how advancements in telemetric monitoring of blood pressure and heart rate have led to several major discoveries in the field of cardiovascular research, primarily hypertension and associated pathologies. The benefits of telemetry as a reliable

chronic experiments using different transmitter types.

individual suffering avoided.

**4. Conclusion** 


Applications of Telemetry in Small Laboratory Animals for Studying Cardiovascular Diseases 195

Johnston, N.A., Bosgraaf, C., Cox, L., Reichensperger, J., Verhulst, S., Patten, C. Jr & Toth, L.A.

Kim, H.S., Krege, J.H., Kluckman, K.D., Hagaman, J.R., Hodgin, J.B., Best, C.F., Jennette, J.C.,

*United States of America*, Vol. 92, No. 1, pp. 2735–2739, ISSN 0027-8424. Kramer, K., Kinter, L., Brockway, B.P., Voss, H.P., Remie, R. & Van Zutphen, B.L. (2001). The

*Topics in Laboratory Animal Science*, Vol. 40, No. 1, pp. 8-16, ISSN 1060-0558. Kramer, K. & Kinter, L.B. (2003). Evaluation and applications of radiotelemetry in small

Kurtz, T.W., Griffin, K.A., Bidani, A.K., Davisson, R.L., Hall, J.E. AHA Council on High Blood

Lee, D.L., Leite, R., Fleming, C., Pollock, J.S., Webb, R.C. & Brands, M.W. (2004). Hypertensive

Mancia, G., Ferrari, A., Gregorini, L., Parati, G., Pomidossi, G., Bertinieri, G., Grassi, G., Di

Marler, J.R., Price, T.R. & Clark, G.L. (1989). Morning increases in onset of ischemic stroke.

Marro, M.L., Scremin, O.U., Jordan, M.C., Huynh, L., Porro, F., Roos, K.P., Gajovic, S., Baralle,

Meijer, J.H. & Rietveld, W.J. (1989). Neurophysiology of the suprachiasmatic circadian

Mills, P.A., Huetteman, D.A., Brockway, B.P., Zwiers, L.M., Gelsema, A.J.M., Schwartz, R.S. &

Moons, C.P., Hermans, K., Remie, R., Duchateau, L. & Odberg, F.O. (2007). Intraperitoneal

unguiculatus). *Laboratory Animals*, Vol. 41, No. 2, pp. 262-9, ISSN 0023-6772.

*Physiological Reviews*, Vol. 69, No. 1, pp. 671–707, ISSN 0031-9333.

*Laboratory Animals*, Vol. 41, No. 3, pp. 388-402, ISSN 0023-6772.

Vol. 25, No. 1, pp. 478–479, ISSN 1079-5642.

Vol. 44, No. 3, pp. 259-63, ISSN 0194-911X.

Vol 53, No. 1, pp 96–104, ISSN 0009-7330.

Vol. 36, No. 3, pp. 449-53, ISSN 0194-911X.

pp. 1537–1544, ISSN 8750-7587.

0194-911X.

of menopause-associated hypertension. *Hypertension*, Vol. 42, No. 4, pp. 761-7, ISSN

(2007). Strategies for refinement of abdominal device implantation in mice: strain, carboxymethylcellulose, thermal support, and atipamezole. *Journal of the American Association for Laboratory Animal Science*, Vol. 46, No. 2, pp. 46-53, ISSN 1060-0558. Kaïdi, S., Brutel, F., Van Deun, F., Kramer, K., Remie, R., Dewé, W., Remusat, P., Delaunoism

A. & Depelchin, O. (2007). Comparison of two methods (left carotid artery and abdominal aorta) for surgical implantation of radiotelemetry devices in CD-1 mice.

Coffman, T.M., Maeda, N. & Smithies, O. (1995). Genetic control of blood pressure and the angiotensinogen locus. *Proceedings of the National Academy of Sciences of the* 

use of radiotelemetry in small laboratory animals: recent advances. *Contemporary* 

laboratory animals. *Physiological Genomics*, Vol. 13, No. 3, pp. 197-205, ISSN 1094-8341.

Pressure Research, Professional, & Public Education Subcommittee. (2005). Recommendations for blood pressure measurement in animals: summary of an AHA scientific statement from the Council on High Blood Pressure Research, Professional, and Public Education Subcommittee. *Arteriosclerosis, Thrombosis, and Vascular Biology*,

response to acute stress is attenuated in interleukin-6 knockout mice. *Hypertension*,

Rienzo, M., Pedotti, A. & Zanchetti, A. (1983). Blood pressure and heart rate variabilities in normotensive and hypertensive human beings. *Circulation Research*,

*Stroke*, Vol. 20, No. 1, pp. 473–476Meijer, J.H. & Rietveld, W.J. (1989). Neurophysiology of the suprachiasmatic circadian pacemaker in rodents.

F.E. & Muro, A.F. (2000). Hypertension in beta-adducin-deficient mice. *Hypertension*,

pacemaker in rodents. *Physiologival Reviews*, Vol. 69, No. 3, pp. 671-707, ISSN 0031-9333.

Kramer, K. (2000). A new method for measurement of blood pressure, heart rate, and activity in the mouse by radiotelemetry. *Journal of Applied Physiology*, Vol. 88, No. 1,

versus subcutaneous telemetry devices in young Mongolian gerbils (Meriones

activation in paraventricular nucleus of mice with renovascular hypertension. *Hypertension*, Vol. 57, No. 2, pp. 289-97, ISSN 0194-911X.


Buñag, R.D. (1984). Measurement of blood pressure in rats. In: W. de Jong (Ed.), Handbook of

Butz, G.M. & Davisson, R.L. (2001). Long-term telemetric measurement of cardiovascular

Campos, L.A., Plehm, R., Cipolla-Neto, J., Bader, M. & Baltatu, O.C. (2006). Altered circadian

Carlson, S.H. & Wyss, J.M. (2000). Long-term telemetric recording of arterial pressure and

Chasen, C. & Muller, J.E. (1998). Cardiovascular triggers and morning events. *Blood Pressure* 

Conway, J., Boon, N., Davies, C., Jones, J.V. & Sleight, P. (1984). Neural and humoral

Gauvin, D.V., Tilley, L.P., Smith, F.W. Jr. & Baird, T.J. (2006). Electrocardiogram,

Greene, A.N., Clapp, S.L. & Alper, R.H. (2008). Timecourse of recovery after surgical

Grundt, C., Meier, K. & Lemmer, B. (2006). Gender dependency of circadian blood pressure

Hawkins, P., Morton, D.B., Bevan, R., Heath, K., Kirkwood, J., Pearce, P., Scott, L., Whelan, G.,

Hoffmann, D.S., Weydert, C.J., Lazartigues, E., Kutschke, W.J., Kienzle, M.F., Leach, J.E.,

of preeclampsia. *Hypertension*, Vol. 51, No. 4, pp. 1058-65, ISSN 0194-911X. Javeshghani, D., Touyz, R.M., Sairam, M.R., Virdis, A., Neves, M.F. & Schiffrin, E.L. (2003).

*Chronobiology International*, Vol. 23, No. 4, pp. 813-29, ISSN 0742-0528.

*Comparative Physiology*, Vol. 290, No. 4, pp. R1122-7, ISSN 0363-6119.

*Hypertension*, Vol. 57, No. 2, pp. 289-97, ISSN 0194-911X.

*Monitoring*, Vol. 3, No. 1, pp 35–42, ISSN 1359-5237.

*Methods*, Vol. 53, No. 2, pp. 128-39, ISSN 1056-8719.

12). Elsevier, New York, ISBN 0444897151.

5, No. 2, pp. 89-97, ISSN 1094-8341.

1, pp. 203–208, ISSN 0263-6352.

955-61, ISSN 0263-6352.

0023-6772.

ISSN 0194-911X.

activation in paraventricular nucleus of mice with renovascular hypertension.

Hypertension, Volume 4: Experimental and genetic models of hypertension (pp. 1–

parameters in awake mice: a physiological genomics tool. *Physiological Genomics*, Vol.

rhythm reentrainment to light phase shifts in rats with low levels of brain angiotensinogen. *American Journal of Physiology - Regulatory, Integrative and* 

heart rate in mice fed basal and high NaCl diets. *Hypertension*, Vol. 35, No. 2, pp. E1-5,

mechanisms involved in blood pressure variability. *Journal of Hypertension*, Vol. 2, No.

hemodynamics, and core body temperatures of the normal freely moving laboratory beagle dog by remote radiotelemetry. *Journal of Pharmacological and Toxicological* 

intraperitoneal implantation of radiotelemetry transmitters in rats. *Journal of Pharmacological and Toxicological Methods*, Vol. 56, No. 2, pp. 218-22, ISSN 1056-8719. Gross, V., Milia, A.F., Plehm, R., Inagami, T. & Luft, F.C. (2000). Long-term blood pressure

telemetry in AT2 receptor-disrupted mice. *Journal of Hypertension*, Vol. 18, No. 7, pp.

and heart rate profiles in spontaneously hypertensive rats: effects of beta-blockers.

Webb, A. & Joint Working Group on Refinement. (2004). Husbandry refinements for rats, mice, dogs and non-human primates used in telemetry procedures. Seventh report of the BVAAWF/FRAME/RSPCA/UFAW Joint Working Group on Refinement, Part B. *Laboratory Animals*, Vol. 38, No. 1, pp. 1-10, ISSN 0023-6772. Hess, P., Rey, M., Wanner, D., Steiner, B. & Clozel, M. (2007) Measurements of blood pressure

and electrocardiogram in conscious freely moving guineapigs: a model for screening QT interval prolongation effects. *Laboratory Animals*, Vol. 41, No. 4, pp. 470-80, ISSN

Sharma, J.A., Sharma, R.V. & Davisson, R.L. (2008). Chronic tempol prevents hypertension, proteinuria, and poor feto-placental outcomes in BPH/5 mouse model

Attenuated responses to angiotensin II in follitropin receptor knockout mice, a model

of menopause-associated hypertension. *Hypertension*, Vol. 42, No. 4, pp. 761-7, ISSN 0194-911X.


**Part 4** 

**Medical Telemetry**

