Chemically induced model of hypermethioninemia in rats

In the present study, we developed a chronic chemically induced model of hypermethioninemia in rats. We induced elevated concentrations of methionine in the blood by injecting subcutaneously methionine (1.34–2.68 μmol/g of body weight) to developing animals of various ages. Brain methionine concentrations were approximately 1.25 μmol/g wet tissue (∼1.0 mM). We then injected the same doses of methionine to young rats twice a day at 8 h intervals from the 6th to the 28th postpartum day. Controls received saline in the same volumes. The body, brain and hippocampus of rats were weighed after treatment and showed that hypermethioninemic animals had no differences in these parameters, when compared to the control group, suggesting that methionine did not cause malnutrition in the rats. Considering that experimental animal models are useful to understand the pathophysiology of human disease, the present model of hypermethioninemia may contribute to the investigation of the mechanisms of brain damage caused by high tissue methionine levels.