[The role of human atrial natriuretic peptide on pathogenesis of nephropathy in patients with type I diabetes mellitus].

Divergent findings in recent clinical and experimental studies have caused considerable controversy as to whether or how elevated plasma levels of human atrial natriuretic peptide (hANP) may contribute to the pathogenesis of diabetic nephropathy in type I diabetic patients. Therefore, we decided to examine potential changes of urinary albumin excretion (UAE), urinary excretion of alpha-1-microglobulin (A-1-M), mean arterial blood pressure (MAP), hANP levels, creatinine clearance and HbA1 in the course of a prospective one-year study in 19 patients (13 females, six males, age 29 +/- 2 years). All patients had intensified insulin treatment. Seven patients at increased risk for eventually developing nephropathy (group 1) were identified by repeatedly showing elevated UAE ( > 30 mg/24 h). The other patients served as controls (group 2). Patients in group 1 differed from those in group 2 in increased A-1-M (maximal difference, 10.1 +/- 1.5 vs. 5.5 +/- 1.0 mg/l, p < 0.01). In the second half of the study, 43% of the MAP measurements in group 1 exceeded 100 mmHg in comparison to 19% in group 2 (p < 0.01). Simultaneously, 38% of the hANP levels in plasma in group 1 were higher than 25 pg/ml (upper limit of normal range) in comparison to 15% in group 2 (p < 0.05). There were no differences in creatinine clearance between both groups. 58% of the HbA1 concentrations measured in group 1 in the course of the study exceeded 8.5% in comparison to 47% in group 2 (p < 0.05).(ABSTRACT TRUNCATED AT 250 WORDS)