摘要
目的研究高G值作用后是否会造成豚鼠前庭功能紊乱 ,以及预先低G值暴露的预适应是否会对此有预防作用。方法 86只豚鼠随机分为空白对照组 (1 0只 ) ,1 0Gy组 (2 8只 ) ,2G组 (2 0只 ) ,预适应组 (2 8只 ) ,共 4组。 1 0Gy组直接给予 1 0Gy 5min暴露 ,2G组给予 8d 2G暴露 (1 0h/d) ,预适应组 (2 8只 )给予 8d 2G暴露后再给予 1 0Gy 5min暴露 ,对照组不给任何刺激。每组刺激后观察各豚鼠的行为学及前庭躯体和前庭眼动反射 ,包括有无头位震颤 ,头位偏斜 ,身体侧滚和转圈 ,有无自发眼震及眼位偏斜等前庭受损表现 ,并记录其持续时间。随后 (刺激后约 0 .5h)每组各取 8只用免疫组化方法观察前庭中枢核团ChAT活性并进行灰度分析 ,其余用于其它指标研究。结果 +1 0Gy 5min的暴露 (+1 0Gy组 )可引起2 2 / 2 8(79% )豚鼠前庭行为学的异常 ,包括自发眼震、眼位偏斜、头位震颤、头位偏斜、身体转圈、侧滚转等 ;而在给予 +1 0Gy 5min的暴露前经过预适应 (预适应组 )的行为异常率只有 1 4/ 2 8(5 0 % ) ,两组之间具有显著差别 (P <0 .0 5 )。两组ChAT染色均明显高于对照组 (P <0 .0 1 ) ,不过两组之间未见明显差别。结论高G值作用可引起豚鼠前庭功能障碍 ,预适应具有一定的防护作用 ,中枢神经递质ChAT变化可能与此有一?
Objective To explore if high G exposure can cause vestibular disorder in guinea pig and the possibility of preventing it by preconditioning with exposure to a low hypergravity environment before high G stimulus. Method A total of 86 guinea pigs were divided into 4 groups: 1)28 were treated with a stimulus of +10 Gy for 5 min (+10 Gy group);2)28 were preconditioned by exposure to 2 G environment for 8 d before the +10 Gy stimulus (preconditioning group); 3)20 were exposed to 2 G environment for 8 d, but without +10 Gy stimulus (2 G group); the rest 10 served as control. Their vestibular related behaviour, including vestibulo spinal reflex (VSR) and vestibulo ocular reflex (VOR) such as head tremble, head deviation, spontaneous nystagmus, eye deviation, body tilt or looping, were observed directly, the choline acetyltransferase(ChAT) activity in VNC (vestibular nucleon complex) in brain stem were investigated by immunohistochemistry technique, and the relative gamma in each group were analysed. Result The incidence of behavioral abnormalities (BA) in 10 Gy group(79%) is significantly higher than that in preconditioning group(50%).The relative gamma of staining showed that the content of ChAT in VNC of the +10 Gy group and preconditioning group were significantly higher than that in control group, but no difference was found between them in +10 Gy and preconditioning groups. Conclusion High G exposure of +10 Gy for 5 min could cause vestibular disorders in guinea pigs, and preconditioning with pre exposure to 2 G environment could alleviate it. ChAT activity changes in VNC may contribute to its mechanisms.
出处
《航天医学与医学工程》
CAS
CSCD
北大核心
2003年第2期88-92,共5页
Space Medicine & Medical Engineering
关键词
高G值
前庭功能障碍
耳石器
预适应
胆碱乙酰化酶
高加速度
免疫组织化学
行为学
high acceleration
vestibular function tests
preconditioning
behavior
choline acetyltransferase(ChAT)
immunohistochemistry Address reprint requests to:JIA Hong bo.Institute of Aviation Medicine,Beijjing 100036,China
