The use of nonhuman primate models to understand processes in Parkinson's disease.

Research with animal models has led to critical health advances that have saved or improved the lives of millions of human beings. Specifically, nonhuman primate's genetic and anatomo-physiological similarities to humans are especially important for understanding processes like Parkinson's disease, which only occur in humans. Unambiguously, the unique contribution made by nonhuman primate research to our understanding of Parkinson's disease is widely recognized. For example, monkeys with 1-methyl-4-phenyl-1,2,3,6-tetrahydropyridine (MPTP) parkinsonisms are responsive to dopamine replacement therapies, mimicking what is seen in PD patients. Moreover, groundbreaking neuroanatomical and electrophysiological studies using this monkey model in the 1980s and 1990s enabled researchers to identify the neuronal circuits responsible for the cardinal motor features of PD. This led to the development of subthalamic surgical ablation and deep brain stimulation, the current therapeutic gold standard for neurosurgical treatment. More recently, the mechanisms of α-synuclein spreading testing the prion hypothesis for PD have yielded exciting results. In this review, we discuss and highlight how the findings from nonhuman primate research contribute to our understanding of idiopathic Parkinson's disease.