AQP2 and diabetic kidney disease: Linear regression analysis of the histological diagnosis and exosomal excretion of AQP5 and AQP2 in the urine (UAQP5 and UAQP2) of patients with non-diabetic proteinuric nephropathy (NDN) and diabetic nephropathy showed that UAQP5 and UAQP2 were positively correlated with the histological type of diabetic nephropathy (148).