PLASMA ATRIAL-NATRIURETIC-PEPTIDE LEVELS IN RABBITS WITH ALLOXAN MONOHYDRATE-INDUCED DIABETES-MELLITUS

The effect of alloxan monohydrate-induced diabetes on the resting plas ma atrial natriuretic peptide (ANP) level was investigated in 22 male New Zealand white rabbits. Alloxan monohydrate (100 mg/kg) dissolved i n saline at a concentration of 50 mg/ml was administered by a single i ntravenous injection 3 months before the experimental analysis. The di abetic state was examined 72 h later by quantitative determination of blood glucose levels of >350 mg/dl. Beginning on day 3, 14 animals (Gr oup 1) received a daily subcutaneous injection of 1 U insulin having m oderate hyperglycemia (blood glucose concentration [BGC] between 300 a nd 400 mg/dl). Eight animals (Group 2; normoglycemic controls) receive d 3.2 U of insulin daily to maintain the BGC below 100 mg/dl. Eight he althy rabbits were included in the study as controls (Group 3). Blood samples for ANP analysis were obtained three months after administrati on of alloxan monohydrate.The plasma ANP levels in moderately diabetic rabbits (328 +/- 43 pg/ml) were significantly higher than those in no rmoglycemic (98.5 +/- 20 pg/ml) and healthy (76.6 +/- 18 pg/ml) contro ls (P < 0.001 for both). In addition, we found a significant correlati on between plasma levels of glucose and levels of ANP (r = 0.665, P < 0.001). Our data indicate that further experiments need to be performe d to investigate what is responsible for the elevation of plasma ANP l evels in diabetic rabbits.