Increased ENaC activity during kidney preservation in Wisconsin solution

Area of Science:

• Nephrology
• Transplantation Biology
• Molecular Physiology

Background:

• Effective kidney preservation solutions are crucial for transplantation success.
• The University of Wisconsin (UW) solution is the current gold standard but has limitations in extending organ viability.
• The impact of UW solution on epithelial Na+ channel (ENaC) activity remains largely unknown.

Purpose of the Study:

• To investigate the effect of UW solution on ENaC activity in preserved kidneys.
• To determine if UW solution affects ENaC protein expression or mRNA transcription.
• To assess the implications of observed changes for post-transplant allograft function.

Main Methods:

• Kidney samples from Sprague Dawley rats and dogs were preserved in UW solution for varying durations.
• Epithelial Na+ channel (ENaC) activity was measured using patch clamp techniques.
• Protein expression (Western blot) and mRNA levels (RT-qPCR) of ENaC were analyzed, alongside lactate dehydrogenase (LDH) levels.

Main Results:

• Kidney preservation in UW solution led to reduced kidney size and weight, and elevated LDH levels.
• Patch clamp analysis revealed a significant increase in ENaC activity in both rat and dog kidneys.
• No significant changes were observed in ENaC channel mRNA levels during preservation.

Conclusions:

• ENaC activity is markedly elevated in kidneys preserved with UW solution.
• This elevated ENaC activity may negatively influence immediate post-implantation allograft function.
• Understanding these effects is critical for optimizing kidney preservation strategies and improving transplant success rates.