SCIATIC-NERVE ATPASE ACTIVITY IS UNAFFECTED IN DIABETIC MUTANT C57BL/KS (DB/DB) MICE

We investigated composite (total), Mg2+ (ouabain-resistant), and Na+-K+-(ouabain-inhibited) ATPase in sciatic nerves of diabetic mutant C57BL/Ks (db/db) and age-related littermate (db/+) control mice at various ages (16, 26, and 40 wk). This is the first report indicating that nerve ATPase activities measured in vitro showed no deficit in mice with spontaneous diabetes. Thus, diabetic neuropathy in the genetically diabetic mouse may occur in the absence of Na+-K+-ATPase abnormalities, which were previously described in association with polyol pathway impairment in experimental diabetic and BB Wistar rats. Control and diabetic groups treated with ganglioside mixture for 30 days before death presented statistically insignificant differences. Therefore, the beneficial effect of gangliosides described in C57BL/Ks (db/db) mice on electrophysiological and morphometrical parameters must be due to different pharmacological activites rather than to prevention of the decay or better maintenance of ATPase activity.