A SIMPLE VERSATILE METHOD FOR MEASURING TAIL CUFF SYSTOLIC BLOOD-PRESSURE IN CONSCIOUS RATS

1. The non-invasive measurement of tail cuff systolic blood pressure i n conscious rats is routinely used in long-term cardiovascular studies . There are a number of commercially available tail cuff systems, howe ver, these apparatus are generally expensive and are dedicated for sin gle-task operations, In the present study, a simple method for measuri ng systolic blood pressure, which requires only minor modifications to the existing hardware found in most cardiovascular laboratories, is d escribed. 2. Systolic blood pressure measurements were made in the con ventional manner by determining the systolic blood pressure which coin cided with the restoration of the caudal artery pulse. This was achiev ed by using an inexpensive piezo-electric pulse transducer to detect t he pulse, and this was coupled to a standard data-aquisition system (M acLab(R) ADInstruments) normally set up to record blood pressure, This method was compared with another established tail cuff method, as wel l as with direct intra-arterial recordings. 3. It was found that the r esults obtained using both tail cuff systems were in good agreement wh en systolic blood pressure was measured in Wistar-Kyoto rats and spont aneously hypertensive rats, In addition, systolic blood pressure was m easured over 4 weeks in 2K1C rats and sham-operated rats, with both ta il cuff methods producing similar results, which were not significantl y different from direct intra-arterial recordings in the same animals. 4. Thus, in the present study, with only minor modifications, the sam e equipment was used for both direct and indirect determinations of sy stolic blood pressure, This situation differs from other conventional tail cuff systems since these items are designed for a single purpose, Therefore, the current method using piezo-electric sensor/MacLab(R)-t echnology should be viewed as a relatively simple, flexible and cheap alternative method to measure tail cuff systolic blood pressure in con scious rats.