Randall's Plaque in Stone Formers Originates in Ascending Thin Limbs.

Randall's Plaque in Stone Formers Originates in Ascending Thin Limbs.
Am J Physiol Renal Physiol. 2018 Aug 01;:
Authors: Evan AP, Coe FL, Lingeman JE, Bledsoe SB, Worcester EM
Abstract
Randall's plaque, an attachment site over which calcium oxalate stones form, begins in the basement membranes of the thin limbs of the loop of Henle. The mechanism of its formation is unknown. Possibly, enhanced delivery of calcium out of proximal tubule, found in many stone formers, increases reabsorption of calcium from thick ascending limb into the interstitium around descending vasa recta, that convey that calcium into the deep medulla, and raises supersaturations near thin limbs ('vas washdown'). If true, plaque should form preferentially on ascending thin limbs, which do not reabsorb water. We stained serial sections of papillary biopsies from stone formers for AQP-1 (found in descending thin limb) and CLC-Ka (found in ascending thin limb). Plaque (detected using Yasue stain) co-localized with CLC-Ka but not with AQP-1 (X2 = 464, p<0.001). We conclude that plaque forms preferentially in the basement membranes of ascending thin limbs, fulfilling a critical prediction of the vas wash-down theory of plaque pathogenesis. The clinical implication is that treatments such as low sodium diet or thiazide diuretics that raise proximal tubule calcium reabsorption may reduce formation of plaque as well as calcium kidney stones.
PMID: 30066583 ...

Source: Am J Physiol Renal P... - August 1, 2018 Category: Urology & Nephrology Authors: Evan AP, Coe FL, Lingeman JE, Bledsoe SB, Worcester EM Tags: Am J Physiol Renal Physiol Source Type: research