Abstract
Urinary FN-f before and during L-arginine infusion (LA) was measured by ELISA in39healthy subjects and in NIDDM patients with (NIDDM-II, n=23) or without microalbuminuria (NIDDM-I, n=27). Urinary FN-f before and during LA was isolated by gelatin-affinity column andsubjected to SDS-PAGE, in subjects from the three groups. LA induced a 2 to 3-fold increase of FN-f in the 3 subject groups. FN-f before and during LA in NIDDM-II was higher than that of NIDDM-I, and the latterwas increased compared with control subjects. In all groups, urinary FN-f during LA was significantly correlated with AER and glomerular filtration of albumin, and inversely correlated with tubular reabsorption of albumin. By SDS-PAGE, urinary FN-f was distributed from 10kDa to 120kDa. Compared with controls, the 30kDa fraction of FN-f was relatively decreased and the 48kDa fraction was increased in NIDDM-I. A further relative decrease in the 30kDa fraction was seen in NIDDM-II. These results suggest that the increased urinary FN-f might be related to the development of microalbuminuria in NIDDM. As with diabetic retinopathy, changes in the distribution of molecular size of urinary FN-f in NIDDM warrant the further sophistication.
