Streptozotocin‐induced diabetes is not a model for methylmalonic acidaemia

Summary The streptozotocin‐treated diabetic rat was not found to be a suitable animal model for methylmalonic acidaemia as previously described. Urinary methylmalonic acid (MMA) was measured in adult Wistar rats prior to and following injection of streptozotocin (40 mg/kg). Plasma and tissue MMA levels were measured following the induction of diabetes and compared with data from control rats. MMA levels were determined by a gas chromatographic‐mass spectrometric method (McMurray et al. , 1986). Diabetes was confirmed by the 10 × increase in 24h urine volume; glycosuria; glycaemia; and weight loss. Urinary MMA excreted did not change during the 11 week diabetic period and there was no difference between the pre‐ and post‐diabetic phases ( p <0.05). Plasma and tissue MMA concentrations were not elevated in this diabetic animal model. Also in contrast to earlier reports, the vitamin B 12 levels of the diabetic rats were not elevated compared to controls ( p <0.05).