Data collection and other determinant
proteinuria, albuminuria
Baseline characteristics, medication information, vital signs, and biochemical data will be collected. Body weight will be measured at arrival in the clinic (before the inulin clearance test) and blood pressure will be measured twice in the sitting position before and after the inulin clearance test. Measurements of blood urea nitrogen, creatinine, hematocrit, HbA1c, alanine aminotransferase (ALT), aspartate aminotransferase (AST), proteinuria, and albuminuria are planned at baseline, 4–6 weeks after the start of the trial, and at the end of the trial and will be performed using routine procedures at the clinical chemistry facilities of each hospital. Serum and urinary inulin levels will be measured in the laboratory of SRL Inc. (Aichi, Japan). Serum and urinary PAH levels will be measured using liquid chromatography mass spectrometry (LC–MS/MS) at the Institute of Transformative Bio-Molecules (ITbM), Nagoya University, Aichi, Japan. Urinary angiotensinogen levels will be measured using a sandwich ELISA system at the Department of Pharmacology, Kagawa University, Kagawa, Japan. For quality control and quality assurance, a data monitoring committee is composed and monitoring adherence to the protocol. Auditing trial conduct is scheduled and the process will be independent from investigators and the sponsor.