Histopathological study on effects of potassium aspartate on the hypothalamus of rats

Rats of various ages were treated orally or intraperitoneally with potassium aspartate. The dose required to induce hypothalamic lesion varied considerably by the age of animals and route of administration. Additional experiment, in which the animals were orally treated three times a day with potassium aspartate in dose levels between the maximum safety dose and minimum lesion-producing dose in the preceding single dose study, revealed no hypothalamic lesion at all in any animals of each age group. In this condition, the maximum safety dose was 3--5 times as large as that in single dosage administration experiment. Regarding the safety evaluation of potassium aspartate preparations, brief discussions on some points in extrapolation of the results of the present experimental study to the clinical use were made.