Development of a mouse model of infantile spasms induced by N-methyl-D-aspartate

Using N-methyl-D-aspartate (NMDA) injection, we attempt to develop a mouse model for infantile spasms (IS). Experiments were performed in postnatal 11- to 13-day-old C57 and Balbc mice. In the pilot experiment, mice were injected with different doses of NMDA (7, 15, and 30 mg/kg) to determine the optimal age and convulsant doses of NMDA. In further experiment optimal age mice were divided into five groups: group A, control group that received intraperitoneal injection of physiological saline; group B, convulsion group that was given intraperitoneal NMDA; group C, pretreatment group that received adrenocorticotropin (ACTH) injection (100 IU/kg) 30 min before NMDA administration; group D, electroencephalogram (EEG) group that received EEG recording, group E, performance group that received motor and learning test at different time point after NMDA administration. The behaviors of each group were observed continuously for 3h, the latency and the total numbers of spasms were recorded. Pilot experiments showed that a 15 mg/kg dose of NMDA could induce typical spasm-like seizures in P13 C57 mice, NMDA administration caused anxiety and deficits in motor and cognitive functions at early time and that large doses of ACTH reduced the number of seizures and rating scale (P<0.05). The NMDA mouse model has the following characteristics: age dependency, spasm-like seizures, cognitive impairment and response to ACTH, which fulfills the criteria of an IS model.