Nephrectomy decreases amylin and pramlintide clearance in rats

Amylin is a 37 amino acid hormone, co-secreted with insulin from the pancreatic beta-cell in response to nutrient stimuli. Because the human amylin analog, pramlintide, is being tested in patients with diabetes mellitus, a known risk factor for nephropathy, we examined the role of the kidney on amylin and pramlintide metabolism and action in functionally nephrectomized rats. Nephrectomy markedly altered amylin metabolism: it increased incremental area under the plasma amylin concentration curve 3.6-fold (P<0.001) and increased the elimination half-life from 17+/-1 to 26+/-2 minutes (P < 0.01) after subcutaneous injection of 100 microg amylin. Nephrectomy decreased plasma amylin clearance from 20.3+/-1.1 to 7.9+/-0.4 mL/min (P < 0.0001). Thus, at these doses in the rat, the kidney is important for metabolizing amylin and pramlintide.