Joseph J A, Hunt W A, Rabin B M, Dalton T K
Department of Behavioral Sciences, Armed Forces Radiobiology Research Institute, Bethesda, Maryland 20889-5145.
Radiat Res. 1992 Apr;130(1):88-93.
The present experiments were carried out to determine the effects of energy deposition from energetic iron (56Fe particles, an important component of cosmic rays) on motor behavioral performance and to determine if the observed deficits were caused by alterations in the neostriatum (an important motor control area). Neostriatal function was assessed with two correlated parameters, i.e., motor behavioral performance (wire suspension task), and oxotremorine-enhanced K(+)-evoked release of dopamine from perifused striatal slices. Rats were exposed to one of several doses of 56Fe-particle irradiation (0.10-1.0 Gy) and tested on a wire suspension task at 3-180 days postirradiation. Results indicated that profound decrements occurred in both of these indices. The effects on K(+)-evoked release of dopamine were evident for as long as 180 days after irradiation, and a subsequent experiment indicated that these effects appeared as early as 12 h postirradiation. Since similar findings have been observed in aged rats, the results are discussed in terms of these particles producing a possible accelerated striatal aging effect.
开展本实验的目的是确定高能铁（56Fe粒子，宇宙射线的重要组成部分）的能量沉积对运动行为表现的影响，并确定所观察到的缺陷是否由新纹状体（一个重要的运动控制区域）的改变引起。通过两个相关参数评估新纹状体功能，即运动行为表现（悬线任务）和氧化震颤素增强的钾离子诱发的灌流纹状体切片中多巴胺的释放。将大鼠暴露于几种剂量（0.10 - 1.0 Gy）的56Fe粒子辐射之一，并在辐射后3 - 180天进行悬线任务测试。结果表明这两个指标均出现显著下降。对钾离子诱发的多巴胺释放的影响在辐射后长达180天都是明显的，随后的一项实验表明这些影响在辐射后12小时就最早出现了。由于在老年大鼠中也观察到了类似的结果，因此根据这些粒子可能产生加速纹状体衰老效应来讨论这些结果。
