Effects of aldose reductase inhibitor and vitamin B12 on myocardial uptake of I-123-MIBG in patients with non-insulin-dependent diabetes mellitus

Based on the report that metaiodobenzylguanidine (MIBG) uptake into myocardial sympathetic nerve is useful for evaluation of diabetic heart sympathetic nerve dysfunction, authors examined the effects of epalrestat and vitamin B12 on the uptake. Subjects giving informed consent were 32 NIDDM patients without hypertensive or ischemic heart diseases on examination by 201Tl scintigraphy and others. At 10 min and 4 hr after intravenous injection of 111 MBq of 123I-MIBG, myocardial scintigraphy was performed to obtain the planar images with Siemens ZLC-370 gamma camera, whose data were processed by Shimadzu Scintipack 700 and evaluated by HM=early mean counts in heart (H)/early mean counts in mediastinum (M) and by %WR= (H-M)-(delayed H-delayed M) /(H-M). Epalrestat (150 mg/day) and vitamin B12 (1.5 mg/day) was given to each 16 patients for 3-5 months and 123I-MIBG scintigraphy was again carried out to calculate HM and %WR. As results, HM and %WR were not significantly changed by treatment with epalrestat but were improved with vitamin B12 significantly. (K.H.)