Increased ENaC activity during kidney preservation in Wisconsin solution

Abstract

Background The invention of an effective kidney preservation solution capable of prolonging harvested kidney viability is the core of kidney transplantation procedure. Researchers have been working on upgrading the preservation solution quality aiming at prolonging storage time while maintaining utmost organ viability and functionality. For many years, the University of Wisconsin (UW) solution has been considered the gold standard solution for kidney preservation. However, the lifespan of kidney preservation in the UW solution is still limited. Its impact on the epithelial Na + channel (ENaC) activity and its mediated processes is unknown and the primary goal of this study. Methods Kidneys harvested from 8 weeks old Sprague Dawley rats were divided into 4 groups depending upon the period of preservation in UW solution. Additional analysis was performed using dogs’ kidneys. ENaC activity was measured using patch clamp technique; protein expression and mRNA transcription were tested through Western blot and RT-qPCR, respectively. A colorimetric LDH level estimation was performed at different time points during UW solution preservation. Results Kidney preservation in Wisconsin solution caused reduction of the kidney size and weight and elevation of LDH level. ENaC activity increased in both rat and dog kidneys preserved in the UW solution as assessed by patch clamp analysis. On the contrary, ENaC channel mRNA levels remained unchanged. Conclusions ENaC activity is significantly elevated in the kidneys during preservation in UW solution, which might affect the immediate post-implantation allograft function and trajectory post-transplant.

NOX4‐dependent regulation of ENaC in hypertension and diabetic kidney disease

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Vibrodissociation method for isolation of defined nephron segments from human and rodent kidneys

“…Quantitative RT-PCR analysis of the purity of rat tubule fractions was performed using specific markers. The expression of selected genes was quantified by quantitative RT-PCR as previously described (7). Final threshold cycle (C t) values were determined using QuantStudio 6 Flex implemented software and normalized to the housekeeping gene ␤-actin.…”

“…Later, many different modifications of this method as well as new approaches for the isolation of renal tubules have been introduced. Currently, mechanical dissection of nephron segments and enzymatic perfusion (in some cases followed by tissue centrifugation) are among the most widely used approaches for electrophysiological, biochemical, molecular, and fluorescence microscopy studies in renal physiology (7,12,23). However, these methods of separation of nephron components still have considerable limitations.…”

Scanning ion conductance microscopy of live human glomerulus

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