Analysis of urinary protein by immunoblot method using unconcentrated urine in preeclampsia

In order to investigate the renal change in preeclampsia, molecular weight and specific protein analyses in unconcentrated urine were performed by the immunoblot method. Urine samples were taken from 34 preeclamptic cases (pure type), including 20 severe cases. Polypeptide profiles of urine consisted of four patterns: low MW (L) pattern (tubular damage), high MW (H) pattern (glomerular damage), high and low MW (HL) pattern, and middle MW (M) pattern. The incidences of the HL, H, L, and M patterns were 26.5%, 14.7%, 11.8%, and 47.1%, respectively. The HL pattern was found more frequently in severe proteinuria than in mild proteinuria. High incidences of the HL and H patterns were found in the hypertensive group. Larger amounts of IgM, fibronectin, IgG, and beta 2 microglobulin in urine were confirmed using specific antibodies. Our results suggest that the immunoblot method makes it possible to differentiate glomerular and tubular damages and to evaluate the severity of renal damage in preeclampsia using unconcentrated urine.