Estrogen and movement disorders

Female sex hormones, and more specifically estrogen, can have biochemical a nd behavioral effects on the dopaminergic system. The effects of estrogen o n the dopaminergic system can be classified as either neuroprotective or sy mptomatic. The neuroprotective effects refer to the ability of estrogen to prevent or modulate insults to the dopaminergic system and therefore to alt er the natural history of disease processes affecting the dopaminergic circ uitry in the brain. With regard to the symptomatic effects, support for sup pressive and enhancing effects has been documented in humans and laboratory animals. The preclinical literature for neuroprotective and symptomatic ef fects of estrogen on the mesostriatal dopaminergic system forms the basis f or studies on the influence of estrogen on the prevalence, disease progress ion, clinical signs, and medication effects of movement disorders, includin g Parkinson's disease, chorea, dystonia, ties, and myoclonus, Understanding the role of estrogen in modulating the dopaminergic system will allow clin icians to tailor therapies for women with movement disorders and optimize t herapies for menstrually related symptom fluctuations. Such clarifications may also guide recommendations on the use of postmenopausal hormonal replac ement therapy in women with movement disorders or those genetically at risk .