The Indus Doppler Flow Velocity System is a high-frequency, real-time pulsed Doppler measurement device with integrated data analysis software designed for measuring cardiovascular function in small animals. The high sampling rates grant excellent temporal resolution, making this the ideal system for studying fast heart rates and rapid blood accelerations present in small animals. Hardware components include the Pulsed Doppler Transceiver (PDT), a 10 & 20 MHz switchable dual channel system, Doppler Signal Digitizer (DSD) and Doppler Workstation (DW).

Pulsed Doppler signals from the PDT are digitized at high sampling rates by the DSD and the workstation software. The acquired signals are processed using a fast Fourier transform algorithm and displayed as real-time grayscale Doppler flow velocity spectrograms. The workstation software permits recording and analysis of these spectrograms, ideal for report generation and publication purposes. This system has been successfully used in publications with mice, rats, bats, naked mole rats and other small animals. It is also capable of measuring blood flow velocities in larger animals using our implanted extra-vascular Doppler cuff probes.

• Serial measurements or measures responsive to interventions can be made

• Cardiac systolic and diastolic function can be assessed under various conditions

• Superior Pulse Wave Velocity with simultaneous abdominal and aortic velocity measurements to assess Arterial Stiffness

• Severity of transverse aortic constriction (TAC) can be assessed by comparing left and right carotid velocities

• Pressure gradient across TAC can be estimated using stenotic jet velocity

• Induced responses in microvascular beds can be measured through pulsatility and resistivity indices

• Hyperemic velocity responses can be evaluated by assessing coronary flow reserve, a function of cardiac work affected by disease, age, and pressure/volume overload conditions

• Banding effectiveness and coronary reserve measured with Hyperemic/Baseline velocity relations

• Coronary flow distributions can be assessed through changes in the systolic/diastolic flow ratio

Anti-aging gene klotho deficiency promoted high fat diet-induced arterial stiffening via inactivation of AMP-activated protein kinase. Lin Y, Chen J, Sun Z. Hypertension, 67:564-573, (2016). PMID: 26781278

And the beat goes on: attenuated cardiovascular aging in the longest-lived rodent,the naked mole-rat.

Grimes KM, Reddy AK, Lindsey ML, Buffenstein R. Am J Physiol Heart Circ Physiol, 307:H284-H291, (2014).PMID: 24906918

Inhibition of glycosphingolipid synthesis ameliorates atherosclerosis and arterial stiffness in apolipoprotein E-/- mice and rabbits fed a high-fat and -cholesterol diet.Chatterjee S, Bedja D, Mishra S, Amuzie C, Avolio A, Kass DA, Berkowitz D, Renehan M. Circulation, 129:2403-2413,(2014). PMID: 24710030 Rnd3 haploinsufficient mice are predisposed to hemodynamic stress and develop apoptotic cardiomyopathy with heart failure.

Yue X, Yang X, Lin X, Yang T, Yi X, Dai Y, Guo J, Li T, Shi J, Wei L, Fan GC, Chen C, Chang J. Cell Death Disease, 5:e1284,(2014). PMID: 24901055 Genetic deficiency of anti-aging gene klotho exacerbates early nephropathy in STZ-induced diabetes in male mice.

Lin Y, Kuro-o M, Sun Z. Endocrinology, 154:3855-3863, (2013). PMID: 23928372 Hartley CJ, Reddy AK, Madala S, Entman ML, Michael LH, Taffet GE. Am J Physiol Heart Circ Physiol, 301: H269-H278, (2011). PMID: 21572013 Pulsed Doppler signal processing for use in mice: applications.

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