PROTEINURIC POTENTIALS OF ANGIOTENSIN-II, [DES-ASP(1)]-ANGIOTENSIN-II, AND [DES-ASP(1), DES-ARG(2)]-ANGIOTENSIN-II IN RATS

To compare proteinuric potentials among angiotensin II (ANG II) and it s fragments, [des-Asp(1)]-angiotensin II (ANG III) and [des-Asp(1), de s-Arg(2)]-angiotensin II (ANG IV), the peptide was intravenously infus ed for 30 min at doses of 0.015, 0.05, 0.15, 0.45 and 1.45 nmol/kg bod y weight/min. The infusion of ANG II and ANG III increased the fractio nal clearance of albumin in a dose-dependent manner: most extensively for ANG II, and moderately for ANG III. In contrast, the infusion of A NG IV hardly show ed any proteinuric action, even at the maximal dose of 1.45 nmol/kg body weight/min. These results denoted that the cleavi ng of the N-terminal aspartic acid(1) from ANG II weakened the protein uric action in the glomeruli, and the further cleaving of the N-termin al arginine(2) frost ANG III led to a complete loss of proteinuric act ion in the glomeruli.