To elucidate the mechanism behind the increased plasma atrial natriuretic factor (ANF)
reported in Type 1 diabetic patients with glomerular hyperfiltration and incipient
nephropathy, we studied the effects of a short-term moderate hyperglycemia with concomitant
hyperinsulinaemia on plasma ANF concentrations and glomerular filtration rate (GFR)
in healthy male volunteers. Following a 2-hour basal run-in period, blood glucose
level was clamped at 12.2 mmol/l for 4 hours by infusing 20% glucose solution (hyperglycaemia
study) or the level was kept normal by infusing isotonic saline over the 4 hours (saline
control study). Plasma ANF increased slightly both in the hyperglycaemia phase (from
25.7 ± 6.3 to 32.1 ± 7.5 ng/l at 3 hours [p < 0.02] and 31.0 ± 6.6 ng/l at 4 hours
[p = 0.058, mean ± SD]) and in the control phase (from 17.7 ± 6.1 to 26.1 ± 13.5 ng/l
at 3 hours [p < 0.05] and 25.4 ± 11.7 ng/l at 4 hours [p < 0.05]) as compared with
the respective baseline values. GFR remained unchanged both in the hyperglycaemia
(from 108 ± 8 to 104 ± 13 ml/min/1.73 m2) and the saline control phases (from 106 ± 7 to 101 ± 7 ml/min/1.73 m2), respectively. The results of this short-term study showed no association between
the moderate hyperglycaemia with a concomitant hyperinsulinaemia and plasma ANF concentration
in non-diabetic normotensive subjects.
Hyperglycaemia - Hyperinsulinaemia - Atrial Natriuretic Factor