Evaluation of urinary Tamm-Horsfall protein in post-menopausal diabetic women.

Tamm-Horsfall protein (THP), a glycoprotein produced in the thick ascending limb (TAL) and the early distal convoluted tubule (DCT), is normally excreted in large amounts in urine. Urinary THP may be a useful marker for renal damage. The goal of this research project was to determine the THP excretion in control and diabetic post-menopausal women. Twenty-four hour urine samples were collected from 19 controls and 19 diabetic patients (11 non-insulin dependent diabetic mellitus (non-IDDM) patients, and 8 insulin dependent diabetic mellitus (IDDM) patients). Polyacrylamide gel electrophoresis (PAGE), Western blotting, and enzyme linked immunosorbent assay (ELISA) methods were used. It was determined that urinary THP concentrations were significantly decreased in patients with IDDM compared to patients with non-IDDM and controls. In conclusion, laboratory quantitation of urinary THP may be a useful indicator of cellular abnormalities such as reduced protein (THP) synthesis of the cells of the TAL and early DCT in some IDDM patients.