大鼠侧位液压冲击脑损伤动物模型的病理生理学观察

THE ESTABLISHMENT OF A MODIFIED LATERAL FLUID PERCUSSION MODEL OF EXPERIMENTAL BRAIN INJURY IN THE RAT AND PATHOPHYSIOLOGIC STUDY

目的 :建立一种重复性好的大鼠分级侧位液压冲击脑损伤模型 ,为进一步研究外伤性脑损伤的分子机制提供物质基础。方法 :雄性SD大鼠 ,随机分为正常对照组、手术对照组和损伤组 ;损伤组按冲击力大小分为轻 (1 0 0kPa)、中 (2 0 0kPa)、重 (30 0kPa) 3个亚组。实验中由计算机记录冲击时脑承受的压力曲线并描记大鼠血压和心率变化。结果 :脑承受的压力曲线与冲击气压呈直线正相关 (r =0 .985 ) ,损伤组大鼠在冲击后立即出现去大脑强直和呼吸暂停。中、重度损伤组部分动物发生抽搐 ;损伤组大鼠在冲击后迅速出现短暂血压上升 ,中、重度损伤组动物伴心率减慢并继发血压降低 ;病理学检查可见硬膜外出血、蛛网膜下出血、侧脑室出血以及冲击侧胼胝体出血。冲击压力越大 ,损伤程度越重。结论 :改进后的液压冲击装置可以复制大鼠分级侧位液压冲击脑损伤模型 ,冲击力定量准确 ,重复性好。

Aim: The purpose of the present study is to establish a reproducible graded lateral fluid percussion model of experimental brain injury in the rat to study the molecular mechanism of the traumatic brain injury more concisely. Methods:Male Sprague-Dawley rats were divided into normal control, sham operation control and injury groups which were sub-divided into three subgroups including mild injury group (100kPa), moderate injury group (200kPa) and severe injury groups (300kPa). The data of the percussion pressure wave, the rat's blood pressure and heart rate were recorded. Results: The pressure recorded on the computer was co related po sitively to the percussion gas pressure ( r =0.985); The fluid percussion injury in rats produced a decerebrate posture and apnea. Convulsions were observed in moderate and high magnitude of injury group; Moderate and high magnitudes of injury groups produced acute and transient systemic hypertension with bradycardia followed by hypotension; Gross examination demonstrated subdural hemorrhage, subarachnoid hemorrhage, hemorrhage in lateral ventricle and corpus callosum at the percussion side. The extent of pathologic changes was more severe at the higher magnitudes of injury. Conclusions: The new devices could produce graded reproducible lateral fluid percussion brain injury in rats. The model can be used for the study of neuropathologic and molecular mechanism of brain injury.