[Changes in Tamm-Horsfall protein excretion in the urine of patients with hypertension in pregnancy]

Abstract

In previous studies we detected an intensively stained protein band with an apparent molecular weight of 105 kD in the urinary electrophoresis pattern of healthy control subjects and pregnant women; this protein band was identified as Tamm-Horsfall protein by using Western blot. The aim of the present study was to determine the changes of this THP band in 64 patients with an uncomplicated course of pregnancy and 135 hypertensive pregnant women by use of a special urine preparation and a modified SDS-PAGE. The number of protein bands did not change in the course of pregnancy and in the post partum period. The THP band was constantly found in all these patients independent of the gestational age. In 83% of the hypertensive pregnant women we observed a marked reduction in intensity or complete disappearance of the THP band. These changes correlated significantly with the severity of the disease. Follow-up analyses in 39 of these patients showed, that in 22 cases disappearance of the THP band occurred simultaneously with and in 11 women before clinical manifestation of the disease. In 81 of the 85 hypertensive pregnant women complete reappearance of the THP band was observed 2 to 14 days after delivery. Our findings may reflect a transitory tubular dysfunction in cases of preeclampsia and support the hypothesis of an immunological pathogenesis of the disease.