scholarly journals Regional blood flow measurement with pulsed Doppler flowmeter in conscious rat

1981 ◽  
Vol 241 (2) ◽  
pp. H273-H278 ◽  
Author(s):  
J. R. Haywood ◽  
R. A. Shaffer ◽  
C. Fastenow ◽  
G. D. Fink ◽  
M. J. Brody
Keyword(s):  
Blood Flow ◽  
Vascular Resistance ◽  
Regional Blood Flow ◽  
Pulsed Doppler ◽  
Sound Waves ◽  
Conscious Rat ◽  
Cross Sectional ◽  
Freely Moving ◽  
Flowmeter System ◽  
Doppler Flowmeter

Development of techniques for the continuous measurement of regional blood flow and vascular resistance in intact small animals has been impeded primarily by the bulkiness of flow probes. The availability of an ultrasonic pulsed Doppler flowmeter system enabled us to construct miniaturized probes using 1-mm-diameter piezoelectric crystals that emit a 20-mHz signal and receive the reflected sound waves from passing blood cells. The finished flow probe is approximately 2.5-4 mm long and 2 mm in cross-sectional diameter with lumen diameters appropriate for the rat, ranging from 0.7 to 1.2 mm. This report describes the materials and methods involved in constructing and implanting the probes in rats to monitor renal, mesenteric, and hindquarter blood flow velocity. The accuracy of the pulsed Doppler method in detecting changes in regional blood flow and vascular resistance was established by the demonstration of a highly significant correlation between velocity recorded from the Doppler unit and volume flow recorded simultaneously. These data indicate that the ultrasonic pulsed Doppler flowmeter provides the opportunity to measure changes in regional blood flow and vascular resistance in a conscious freely moving rat.

scholarly journals Analysis of blood flow in pulmonary hypertension with the pulsed Doppler flowmeter combined with cross sectional echocardiography.

Heart ◽  
1984 ◽  
Vol 51 (4) ◽  
pp. 407-415 ◽  
Author(s):  
M Okamoto ◽  
K Miyatake ◽  
N Kinoshita ◽  
H Sakakibara ◽  
Y Nimura
Keyword(s):  
Blood Flow ◽  
Pulmonary Hypertension ◽  
Pulsed Doppler ◽  
Cross Sectional ◽  
Doppler Flowmeter

Sexual dimorphism in regional blood flow responses to vasopressin in conscious rats

1997 ◽  
Vol 273 (3) ◽  
pp. R1126-R1131 ◽  
Author(s):  
Y. X. Wang ◽  
J. T. Crofton ◽  
S. L. Bealer ◽  
L. Share
Keyword(s):  
Blood Flow ◽  
Vascular Resistance ◽  
Regional Blood Flow ◽  
Pressor Response ◽  
Peripheral Resistance ◽  
Female Rats ◽  
Sexually Dimorphic ◽  
Arterial Blood ◽  
Vasoconstrictor Response ◽  
Renal Vascular

The greater pressor response to vasopressin in male than in nonestrous female rats results from a greater increase in total peripheral resistance in males. The present study was performed to identify the vascular beds that contribute to this difference. Mean arterial blood pressure (MABP) and changes in blood flow in the mesenteric and renal arteries and terminal aorta were measured in conscious male and nonestrous female rats 3 h after surgery. Graded intravenous infusions of vasopressin induced greater increases in MABP and mesenteric vascular resistance and a greater decrease in mesenteric blood flow in males. Vasopressin also increased renal vascular resistance to a greater extent in males. Because renal blood flow remained unchanged, this difference may be due to autoregulation. The vasopressin-induced reduction in blood flow and increased resistance in the hindquarters were moderate and did not differ between sexes. Thus the greater vasoconstrictor response to vasopressin in the mesenteric vascular bed of male than nonestrous females contributed importantly to the sexually dimorphic pressor response to vasopressin in these experiments.

Measurement of portal blood flow by an ultrasonic “duplex” system composed of a pulsed Doppler flowmeter and a linear-type real time B mode electroscanner

1988 ◽  
Vol 23 (1) ◽  
pp. 37-43 ◽  
Author(s):  
Shigehiro Shiraki ◽  
Katsuhiko Tsukada ◽  
Norishige Ozeki ◽  
Toshihiko Takeuchi ◽  
Kazuo Gotoh ◽  
...  
Keyword(s):  
Blood Flow ◽  
Real Time ◽  
Portal Blood Flow ◽  
Portal Blood ◽  
Pulsed Doppler ◽  
Duplex System ◽  
Linear Type ◽  
Doppler Flowmeter

Application and In situ calibration of a pulsed-doppler flowmeter for blood flow measurement in crustaceans

1994 ◽  
Vol 74 (2) ◽  
pp. 455-458 ◽  
Author(s):  
C.N. Airriess ◽  
B.R. McMahon ◽  
I.J. McGaw ◽  
G.B. Bourne
Keyword(s):  
Blood Flow ◽  
Cardiac Output ◽  
The Body ◽  
Pulsed Doppler ◽  
Arterial Perfusion ◽  
Non Invasive ◽  
In Situ Calibration ◽  
Flow Through ◽  
Doppler Flowmeter

The pulsed-Doppler flowmeter permits continuous, non-invasive measurement of blood flow through several arteries simultaneously. Summation of volume flow rates through all arteries leaving the heart allows determination of cardiac output, stroke volume, and the percentage of cardiac output delivered to each region of the body. The use of this system for investigating changes in arterial perfusion as well as its calibration in situ are described.

Effects of oxygen on regional hemodynamics in hemorrhagic shock

1996 ◽  
Vol 271 (1) ◽  
pp. H203-H211 ◽  
Author(s):  
H. Bitterman ◽  
V. Brod ◽  
G. Weisz ◽  
D. Kushnir ◽  
N. Bitterman
Keyword(s):  
Blood Pressure ◽  
Blood Flow ◽  
Hemorrhagic Shock ◽  
Vascular Resistance ◽  
Regional Blood Flow ◽  
Biceps Femoris ◽  
Total Blood ◽  
Biceps Femoris Muscle ◽  
Arterial Blood ◽  
Femoris Muscle

This study investigated mechanisms of the hemodynamic effects of oxygen in hemorrhagic shock induced by bleeding 30% of the total blood volume in anesthetized rats. An ultrasonic flowmeter was used to monitor regional blood flow. Changes in tissue perfusion were assessed by the laser-Doppler technique. The inhalation of 100% oxygen induced a significant increase in mean arterial blood pressure (MABP) and vascular resistance in the hindquarters, with a concomitant decrease in blood flow in the distal aorta and biceps femoris muscle. In contrast, oxygen did not change vascular resistance in the superior mesenteric artery (SMA) and renal beds and induced a significant increase in blood flow to the renal artery, SMA, and small bowel in hemorrhaged rats. L-Arginine (100 mg/kg iv) but not D-arginine or the vehicle (0.9% NaCl) completely abolished the effects of oxygen on blood pressure and reversed its effects on blood flow and resistance in the hindquarters and biceps femoris muscle. Administration of the nitric oxide (NO) synthase inhibitor NG-nitro-L-arginine methyl ester (50 mg/kg iv) significantly increased MABP and the resistance in the three vascular beds. Pretreatment of hemorrhaged rats with a superoxide dismutase mimic, the NO-stable radical 2,2,6,6-tetramethylpiperidine-N-oxyl (5 mg/kg iv), resulted in significantly diminished effects of oxygen on hindquarter hemodynamics. These results demonstrate a differential effect of oxygen, which increases vascular resistance in the hindquarters without a significant effect in the splanchnic and renal beds, thus favoring an increase in splanchnic and renal perfusion. It is suggested that inactivation of NO by reactive oxygen species may underlie the effects of oxygen on hindquarter vascular tone during shock.

Relationship between regional lung volume and regional pulmonary vascular resistance

1982 ◽  
Vol 52 (4) ◽  
pp. 914-920 ◽  
Author(s):  
E. M. Baile ◽  
P. D. Pare ◽  
L. A. Brooks ◽  
J. C. Hogg
Keyword(s):  
Blood Flow ◽  
Pulmonary Vascular Resistance ◽  
Vascular Resistance ◽  
Lung Volume ◽  
Regional Blood Flow ◽  
Transpulmonary Pressure ◽  
Simple Relationship ◽  
Volume Curve ◽  
Regional Lung ◽  
Residual Capacity

We have examined the relationship between regional pulmonary vascular resistance (PVRr) and regional lung volume (VLr) to determine whether the decrease in blood flow in the dependent lung (zone 4) was related to lung volume. Regional blood flow (Qr) was measured with radiolabeled macroaggregates at functional residual capacity (FRC) and at transpulmonary pressure of 10 cmH2O (PL10) in 10 anesthetized supine dogs. VLr was determined at FRC by measuring lung density in frozen lung slices and was calculated at PL10 using each dog's pressure-volume curve. We found that when PVRr was expressed as a function of VLr there was not a single relationship between the two. Instead we found two separate U-shaped curves, one at FRC and one at PL10 indicating that the increased vascular resistance at the lung base remained when the lung volume was made uniform by inflation to PL10. This suggests that there is no simple relationship between VLr and PVRr.

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