Proteinurea is a common symptom of nephritis in humans and experimental animals, and is an important marker for evaluating disease severity regardless of the type of nephritis. Moreover, proteinurea is determined as the total amount of protein (serum proteins such as globulins and albumin) excreted into a 16-hour urine collection, which is distinctly more accurate than determining the urinary protein concentration, due to large variations in urine volume between individual animals. The turbidity method is a commonly used urinary protein assay method, because it is accurate, easy, and economical.

However, mouse kidneys leak serum components such as bilirubin, resulting in overestimated urinary protein levels, thus proteinuria is not a suitable marker for the evaluation of nephritis severity. On the other hand, albumin, a serum protein with a relatively small molecular weight, and typically the fi rst protein observed in the urine when kidney dysfunction begins to develop, is a more suitable marker to evaluate the severity of nephritis in mouse models.

Chondrex’s Mouse Urinary Albumin Detection Kit (catalog # 3012) is designed to specifi cally determine mouse albumin in 40 urine samples within 4 hours using a sandwich immunoassay method. In mouse nephritis models, such as immune complex-induced glomerulonephritis (ICGN), a mouse is deemed nephritic if the total albumin content in a 16-hour urine collection is greater than 1 mg. It is important to note that urinary albumin levels can reach up to 50-200 mg in a 16-hour urine collection, depending on the severity of nephritis.