Carriers also had increased cerebrospinal fluid α-synuclein (p = 0.016), worse motor function (p = 0.041), anxiety (p = 0.038), and executive function (p < 0.001).
Tissue levels of serotonin and its major metabolite 5-HIAA remained largely unaltered, and the performance of the α-synuclein overexpressing rats in tests of spatial learning (water maze), anxiety related behavior (elevated plus maze) and depressive-like behavior (forced swim test) was not different from control, suggesting that the impact of the developing axonal pathology on serotonin neurotransmission was relatively mild.
Parkinson's disease, neuropathologically defined by the aggregation of α-synuclein, is characterized by neuropsychiatric symptoms such as depression and anxiety preceding the onset of motor symptoms.
In addition, A53Tα-SYN expressing transgenic mice exhibited increased anxiety-like behaviors under normal conditions and abnormal regulation of DBH expression in response to immobilization stress with abnormal adaptive responses.