TY - JOUR

T1 - Nephron blood flow dynamics measured by laser speckle contrast imaging

AU - von Holstein-Rathlou, Niels-Henrik

AU - Sosnovtseva, Olga V

AU - Pavlov, Alexey N

AU - Cupples, William A

AU - Sørensen, Charlotte Mehlin

AU - Marsh, Donald J

PY - 2011/2/1

Y1 - 2011/2/1

N2 - Tubuloglomerular feedback (TGF) has an important role in autoregulation of renal blood flow and glomerular filtration rate (GFR). Because of the characteristics of signal transmission in the feedback loop, the TGF undergoes self-sustained oscillations in single-nephron blood flow, GFR, and tubular pressure and flow. Nephrons interact by exchanging electrical signals conducted electrotonically through cells of the vascular wall, leading to synchronization of the TGF-mediated oscillations. Experimental studies of these interactions have been limited to observations on two or at most three nephrons simultaneously. The interacting nephron fields are likely to be more extensive. We have turned to laser speckle contrast imaging to measure the blood flow dynamics of 50-100 nephrons simultaneously on the renal surface of anesthetized rats. We report the application of this method and describe analytic techniques for extracting the desired data and for examining them for evidence of nephron synchronization. Synchronized TGF oscillations were detected in pairs or triplets of nephrons. The amplitude and the frequency of the oscillations changed with time, as did the patterns of synchronization. Synchronization may take place among nephrons not immediately adjacent on the surface of the kidney.

AB - Tubuloglomerular feedback (TGF) has an important role in autoregulation of renal blood flow and glomerular filtration rate (GFR). Because of the characteristics of signal transmission in the feedback loop, the TGF undergoes self-sustained oscillations in single-nephron blood flow, GFR, and tubular pressure and flow. Nephrons interact by exchanging electrical signals conducted electrotonically through cells of the vascular wall, leading to synchronization of the TGF-mediated oscillations. Experimental studies of these interactions have been limited to observations on two or at most three nephrons simultaneously. The interacting nephron fields are likely to be more extensive. We have turned to laser speckle contrast imaging to measure the blood flow dynamics of 50-100 nephrons simultaneously on the renal surface of anesthetized rats. We report the application of this method and describe analytic techniques for extracting the desired data and for examining them for evidence of nephron synchronization. Synchronized TGF oscillations were detected in pairs or triplets of nephrons. The amplitude and the frequency of the oscillations changed with time, as did the patterns of synchronization. Synchronization may take place among nephrons not immediately adjacent on the surface of the kidney.

KW - Acetylcholine

KW - Angiotensin II

KW - Animals

KW - Hemodynamics

KW - Lasers

KW - Male

KW - Nephrons

KW - Rats

KW - Rats, Sprague-Dawley

KW - Renal Circulation

KW - Rheology

U2 - 10.1152/ajprenal.00417.2010

DO - 10.1152/ajprenal.00417.2010

M3 - Journal article

C2 - 21048025

VL - 300

SP - F319-29

JO - American Journal of Physiology - Renal Fluid and Electrolyte Physiology

JF - American Journal of Physiology - Renal Fluid and Electrolyte Physiology

SN - 1931-857X

IS - 2

ER -