Further characterisation of the intrastriatal 6-OHDA Parkinson's disease model with non-motor symptom replication and widespread catecholamine dysfunction in male mice

The 6-OHDA mouse model of Parkinson's disease is not well characterised, with variable dosages, injection sites and timeframes. This study further characterised the unilateral intrastriatal 8 μg 6-OHDA mouse model using a four-week protocol, with replication of motor and some non-motor symptoms in male mice. Non-motor symptom replication included cognitive impairment and gastrointestinal dysfunction. Olfactory dysfunction and anxiety-like behaviour were unable to be replicated in this study. Parkinson's disease pathology, particularly non-motor pathology, was also investigated in this study which found the intrastriatal 6-OHDA lesion caused widespread catecholamine dysfunction outside of the nigrostriatal pathway, including the mesocortical and mesolimbic pathway. Proteins involved in neuroinflammation (GFAP), oxidative stress defence (SOD2) and synaptic proteins (SNAP25) were altered, as seen in Parkinson's disease pathology, in the brains of the 6-OHDA lesioned mice.