Long-term memory for aversive training is impaired in Idua−/− mice, a genetic model of mucopolysaccharidosis type I

Mucopolysaccharidosis type I (MPS I) is a lysosomal storage disease that leads to neurodegeneration and neurological deficits, among other pathological and clinical consequences. The aim of the present study was to evaluate neurobehavioral parameters in a genetic mouse model of mucopolysaccharidosis type I (MPS I). During exploration of an open field, adult MPS I (Idua−/−) mice showed normal locomotion and anxiety but reduced number of rearings. Idua−/− mice performed normally in a novel object recognition memory task and showed normal short-term retention of inhibitory avoidance training. By contrast, long-term retention of inhibitory avoidance was impaired in Idua−/− mice. The deficit in inhibitory avoidance memory could not be attributed to reduced footshock reactivity. The results indicate that Idua−/− mice present deficits in long-term memory for aversive training and reduced exploratory behavior.