The
overall experimental setup to acquire Doppler blood
flow velocity data from mice is shown above. The mouse
is anesthetized with Ketamine/Xylazine/Acepromazine
cocktail, Nembutal cocktail, or other anesthetics depending
on the desired type of study.
The mouse is placed in supine position
with its four limbs taped to four electrode plates mounted
on a board. These electrodes are connected via a cable
to the ECG module in a signal processing system that
will provide the mouse ECG signal output.
A 10 MHz pulsed Doppler probe is used
with its tip placed just below the sternum and positioned
to obtain a blood flow velocity signal from the aortic
outlet or mitral inlet. In addition, blood flow velocities
from peripheral arteries of mice can be obtained using
a 20 MHz pulsed Doppler probe. These probes are plugged
into analog pulsed Doppler signal generators (10 or
20 MHz) such as the “Baylor Multichannel High
Frequency Pulsed Doppler Analog Mainframe”. Other
equivalent systems such as those from Crystal Biotech
/ Data Sciences Inc. can also be used. These systems
will generate in-phase and quadrature Doppler demodulated
audio signals.
In the figure above, the Doppler signals
are acquired, processed, and displayed as a real-time
spectrogram along with the ECG signal using the DSPW.
The software also allows the user to perform offline
analysis of the data and to generate reports.
View
Sample Reports from the DSPW |
