title: Effects of HZE particle on the nigrostriatal dopaminergic system in a future Mars mission.
abstract: Because of long duration travel outside the Earth's magnetic field, the effect of iron-rich high charge and energy (HZE) particles in Galactic Cosmic Rays on human body is the major concern in radiation protection. Recently attention has been directed to effects on the central nervous system in addition to mutagenic effects. In particular, a reduction in striatal dopamine content on nigrostriatal dopaminergic system has been reported by investigators using accelerated iron ions in ground-based mammalian studies. In addition, studies of the pathophysiology of Parkinson's disease demonstrated that excess iron cause a reduction in the dopamine content in the substantia nigra. This suggests an intriguing possibility to explain the selective detrimental effects of HZE particles on the dopaminergic system. Should these particles have biochemical effects, possible options for countermeasures are: (1) nutritional prevention, (2) medication, and (3) surgical placement of a stimulator electrode at a specific anatomic site in the basal ganglia.
authors.affiliation: Space Medicine Group, Human Space Technology and Astronaut Department, Japan Aerospace Exploration Agency, Tsukuba, Ibaraki, Japan. koike.yuu@jaxa.jp
authors.forename: Yu
authors.initials: Y
authors.lastname: Koike
authors.forename: M A
authors.initials: MA
authors.lastname: Frey
authors.forename: F
authors.initials: F
authors.lastname: Sahiar
authors.forename: R
authors.initials: R
authors.lastname: Dodge
authors.forename: S
authors.initials: S
authors.lastname: Mohler
mesh_terms: D000818:Animals; D001921:Brain / Q000528:radiation effects*; D002490:Central Nervous System / Q000528:radiation effects; D003342:Corpus Striatum / Q000528:radiation effects; D003359:Cosmic Radiation; D004298:Dopamine / Q000528:radiation effects; D004307:Dose-Response Relationship, Radiation; D005118:Extraterrestrial Environment; D006801:Humans; D007501:Iron; D008297:Male; D018535:Mars; D011829:Radiation Dosage; D011853:Radiobiology; D051381:Rats; D017207:Rats, Sprague-Dawley; D013026:Space Flight; D013378:Substantia Nigra / Q000528:radiation effects
chemical_list: D007501:Iron; D004298:Dopamine