VENOUS COMPLIANCE AND THE VENODILATORY EFFECT OF NITROGLYCERIN IN INSULIN-DEPENDENT DIABETIC-PATIENTS WITH AND WITHOUT (INCIPIENT) NEPHROPATHY

The venous system plays a pivotal role in volume and blood pressure ho meostasis. We tested the hypothesis that the visco-elastic properties of the peripheral venous system are reduced in patients with (incipien t) diabetic nephropathy. Twenty-two normotensive patients with long-te rm insulin-dependent diabetes mellitus (IDDM), 11 without and 11 with (incipient) nephropathy (eight microalbuminuria and three proteinuria, serum creatinine below 100 mu mol l(-1)), and 14 healthy age/sex matc hed controls were studied. Forearm venous compliance (VENCOMP) was det ermined using strain gauge plethysmography and direct intravenous pres sure measurements. Furthermore, the venodilatory effect of 0.4 mg subl ingual nitroglycerin (NTG) was studied. In comparison with healthy con trols, VENCOMP was decreased in patients without and with (incipient) nephropathy, without any differences between the two diabetic groups: 0.059 (0.052-0.066), 0.044 (0.038-0.059) and 0.049 (0.046-0.058) ml 10 0 ml(-1) mmHg(-1), respectively (medians and interquartile ranges) (P < 0.05). No differences in the increase of forearm volume after NTG we re observed: 0.34(0.11-0.51), 0.37 (0.19-0.50) and 0.39 (0.20-0.55) ml 100 ml(-1), respectively. In conclusion, the visco-elastic properties of the peripheral venous system ace reduced in patients with longterm IDDM. This reduction is not related to the presence of nephropathy. N o major differences were observed in NTG-induced venodilation between diabetic patients and healthy subjects.