TY - JOUR

T1 - Functionally induced changes in water transport in the proximal tubule segment of rat kidneys

AU - Faarup, Poul

AU - von Holstein-Rathlou, Niels-Henrik

AU - Nørgaard, Tove

AU - Harrison, Adrian Paul

AU - Bastholm, Lone

AU - Thatt, Lisbeth

AU - Johansen, Flemming Fryd

AU - Hegedüs, Viktor

PY - 2011

Y1 - 2011

N2 - To eliminate freezing artifacts in the proximal tubule cells, two cryotechniques were applied to normal rat kidneys, ie, freeze substitution and special freeze drying. In addition, salt depletion and salt loading were applied to groups of rats to evaluate whether the segmental structure of the proximal tubule could be altered. In the superficial part of the renal cortex of normal kidneys, the typical first segment structure in the proximal tubule was generally present in the early postglomerular fraction of the tubule. However, in the second segment, a special cellular phenomenon was constantly present, comprising a significant intercellular space that was easily identified using a light microscope. In the third segment, in which the presence of basolateral interdigitations is minimal, the small lateral space, which was found to be present in cryopreparations between neighboring cells from the normal kidney, was found to be enlarged by heavy salt loading of short duration. It is concluded that these cryotechniques demonstrate quantitative structural variations between superficial and deep nephrons, as well as the presence of extracellular areas between the cells of the second and the third segment, representing a structural background for the essential transport of water from the proximal tubules to the peritubular capillaries.

AB - To eliminate freezing artifacts in the proximal tubule cells, two cryotechniques were applied to normal rat kidneys, ie, freeze substitution and special freeze drying. In addition, salt depletion and salt loading were applied to groups of rats to evaluate whether the segmental structure of the proximal tubule could be altered. In the superficial part of the renal cortex of normal kidneys, the typical first segment structure in the proximal tubule was generally present in the early postglomerular fraction of the tubule. However, in the second segment, a special cellular phenomenon was constantly present, comprising a significant intercellular space that was easily identified using a light microscope. In the third segment, in which the presence of basolateral interdigitations is minimal, the small lateral space, which was found to be present in cryopreparations between neighboring cells from the normal kidney, was found to be enlarged by heavy salt loading of short duration. It is concluded that these cryotechniques demonstrate quantitative structural variations between superficial and deep nephrons, as well as the presence of extracellular areas between the cells of the second and the third segment, representing a structural background for the essential transport of water from the proximal tubules to the peritubular capillaries.

U2 - 10.2147/IJNRD.S15459

DO - 10.2147/IJNRD.S15459

M3 - Journal article

C2 - 21694951

VL - 4

SP - 73

EP - 84

JO - International Journal of Nephrology and Renovascular Disease

JF - International Journal of Nephrology and Renovascular Disease

SN - 1178-7058

ER -