Structural Organization of Renal Medullary Circulation

Tubular Vascular Endothelial Growth Factor-A, Erythropoietin, and Medullary Vessels

“…1,2 Glomerular capillaries are flanked by high-resistance afferent and efferent arterioles. Two postglomerular capillary networks emerge in series from efferent arterioles.…”

The kidney model as an inverse problem

“…Figures 6, 7). However, the Situation improves drastically, if a "salt transport cascade" [19,62] is included in the model. Such a transport cascade occurs if the upper parts of the long descending limbs of Henle's loops are able to secrete salt actively into the tubulär fluid.…”

From tubular sublimate nephropathy via urinary concentrating mechanism to glomerular disease—Wilhelm Kriz’s contribution to modern nephrology

“…Kriz put much effort into the structural analysis of the vascular and lymphatic system of the kidney in his initial work. Before the functional background of multiple exchange pathways constituting the function of the renal concentrating mechanism, the arrangement of arterial and venous vessel types in the particular kidney zones was pioneering work, allowing understanding of the complex relation between tubular segments, interstitium, and blood vessels in the renal medulla [6,18,39,41,44,45,68,85]. Analyses across several species revealed the structural correlates of wet vs. arid habitats with animals displaying short vs. long papillae and further parenchymal specificities.…”

“…Measuring functional oxygen deficiency together with Joachim Schurek, another long-term collaborator with a physiological and clinical background, was another step towards understanding major questions in medullary function [91]. Achievements on thin limb and vasa recta structures along with these functional insights thus provided the basis for future considerations, particularly regarding the countercurrent exchange processes between vasa recta and the loop segments [24,40,66,69]. The emerging structural concepts on the functions accomplished by the distinct constituents of the renal medulla thus led Kriz and Rex Jamison to express their ideas in a comprehensive and, at that time, very innovative oeuvre termed Burinary concentrating mechanism^ [24], outlining in great detail for the first time how the mammalian kidney forms urine of widely varying solute concentrations (Fig.…”