Preliminary attempts to establish a rat model of striatal injury in glutaric acidaemia type I.

Glutaric acidaemia type I (GA I) is caused by the deficiency of glutaryl-CoA dehydrogenase, resulting in accumulation of glutaric acid (GA) and 3- hydroxyglutaric acid (3-OH-GA) in blood and cerebrospinal fluid (CSF). Neuropathological changes with onset in childhood consist of severe neuronal loss in the caudate and putamen. An animal model is necessary to test possible intervention strategies, and prior reports suggested that GA or 3-OH-GA could be used to create specific neuron loss in adult rats. Adult, 3-week-old and 2-week-old rats received intrastriatal injections of GA and 3-OH-GA at a range of doses. High concentrations caused necrotic lesions in striatum. Low concentrations caused white-matter axonal damage and small areas of neuron loss. Injection of lipopolysaccharide prior to administration of 3-OH-GA was not associated with enhanced neuronal loss. Our findings contradict prior claims and we conclude that the simple model of a single GA or 3-OH-GA injection into rat brain does not replicate the neuropathological findings in humans.