Animal models of Parkinson's disease.

Parkinson's disease (PD) is a disease of an aging population and its etiology is still unknown. In vivo models are attempts to capture as many of the hallmarks of PD as possible. To this end, a number of animal models are in use. These models parallel our thinking about the etiology of PD. Thus, herein, we discuss the most popular neurotoxin animal models, 6-hydroxydopamine and MPTP as one school of thought believes that PD is the result of a toxic insult. Since several researchers think that pesticide and herbicide use can increase the risk of developing PD, we review some of the aspects of rotenone and paraquat in rodents. Furthermore, now that we know that 10% of all PD cases are genetic in nature, we discuss some of the more common genetic rodent models of PD. None of the above models captures all of the hallmarks of PD. Thus, a given model should never be used indiscriminately to investigate every question, but should instead be carefully selected on the basis of being the most suitable model for the question being asked.