INHIBITION OF ALDOSE REDUCTASE - C-13 NMR-STUDIES IN ISOLATED PERIPHERAL-NERVE

We report C-13 MMR measurements of the flux through aldose reductase i n isolated rat sciatic nerve, and its inhibition by an aldose reductas e inhibitor of the sulphonylnitromethane class. [1-C-13] galactose was used as substrate, and the rate of production of [1-C-13] dulcitol wa s measured, Quantitation required the use both of internal extracellul ar, and external, standards. The mean net forward flux (+/- SD) was 20 +/- 11 nmol/(mL nerve water)/min (n = 10). In the presence of the inh ibitor, Bur was reduced significantly (p < 0.001) to 13% of control. S ince dulcitol is symmetrical, an estimate of the backward bu, to [6-C- 13] galactose, is also possible; under our conditions, this was neglig ible.