The BP-2000 Blood Pressure Analysis System™ is the world's leading non-invasive blood pressure analyzer for mice and rats. Its proven technology is now depended on in hundreds of laboratories around the world. More than 500 research papers have been published using the BP-2000.
The BP-2000 Blood Pressure Analysis System was developed for Dr. Oliver Smithies (2007 Nobel Prize in Medicine), to allow him to measure the blood pressure of his groundbreaking transgenic mouse models.
A variety of models for both mice and rats are available to meet every research need.
How it Works
The BP-2000 uses transmission photoplethysmography, in which variations in the amount of light transmitted through the tail is the basic signal that is analyzed to determine the blood pressure and pulse rate.
Every time the heart beats, a pressure wave travels through the vascular system. When it reaches the tail, the vessels dilate slightly, and thus scatter more red light. (This corresponds to systole.) As the pressure wave passes, the vessels in the tail get smaller as the pressure decreases, and less light is scattered. (This corresponds to diastole.) The variation in light transmitted through the tail is what the BP-2000 displays on the computer screen.
Photoplethysmography is very effective at measuring blood pressure on animals ranging from small mice to extremely large rats. And unlike approaches that use a additional sensing cuff (or volume-pressure cuff), photoplethysmography works more reliably with small mouse tails (and does not require two cuffs on the tail).
The diastolic and systolic pressure can be determined by monitoring the vessel dilation as the occlusion cuffs inflates. Here is a plot of actual data showing where diastolic and systolic are measured:
How does it work? Here are two explanations, with progressively more detail:
More Complicated Explanation
When the BP-2000 software has determined the pulse rate, it starts inflating the occlusion cuff. When the occlusion pressure reaches the diastolic pressure, the amplitude of the waveform starts to decrease, since the vessels cannot dilate as much in response to the heartbeat. When the occlusion pressure equals the systolic pressure, the waveform remains at a steady value and thereafter does not decrease, since the vessels cannot dilate at all.
The BP-2000 has been shown in peer-reviewed literature to closely correlate with direct interarterial measurements (Krege JH, Hodgin JB, Hagaman JR, Smithies O, Hypertension. 1995; 25: 1111-1115).
The BP-2000 Analysis Software is the most advanced BP analysis software available. It is easy to use, yet provides all the power you need to make accurate measurements, review and verify your data, and export your results.