The Kidneys Ability to Concentrate and Dilute Urine in Patients With Autosomal Dominant Polycystic Kidney Disease (ADPKD) or Other Cause of Chronic Renal Disease Compared to Healthy Volunteers

The ability to concentrate and dilute urine is primarily regulated via vasopressin (AVP) dependent Aquaporin-2 water channels (AQP2 channels) in the kidney's collecting duct. Autosomal dominant polycystic kidney disease (ADPKD) is a common genetic disorder, characterized by the formation of cyst in the kidneys, causing gradual renal function-loss. Previous studies indicate that ADPKD patients have decreased urine concentration, higher plasma osmolality, and plasma AVP levels compared to healthy controls. Previous studies also indicate that ADPKD patients' dysregulated AVP is an important factor for the pathogenesis and progression of the disease. It is unclear whether ADPKD patients' ability to concentrate and dilute urine are different from those of other cause of chronic renal disease to the same degree. It is also unclear, what mechanisms cause the decreased ability to concentrate and dilute urine in chronic renal disease patients. The purpose of this trial is to investigate the difference in renal function during concentration and dilution test in a case-control, randomized, cross-examination study with ADKPD patients or other cause of chronic renal disease compared to healthy volunteers.