Adelson P D, Dixon C E, Robichaud P, Kochanek P M
Department of Neurosurgery, Children's Hospital of Pittsburgh and The Safar Center for Resuscitation Research, University of Pittsburgh, Pennsylvania, USA.
J Neurotrauma. 1997 Feb;14(2):99-108. doi: 10.1089/neu.1997.14.99.
To determine the motor and cognitive deficits following a diffuse severe traumatic brain injury (TBI) in immature Sprague Dawley rats (17 days), four groups of animals were injured at different severity levels using a new closed head weight drop model: (sham, severe injury [SI: 100 g/2 m], SH [SI + hypoxemia (30 min of an FiO2 of 8% posttrauma)], and ultra severe injury [US: 150 g/2 m]). Latency on beam balance, grip test performance, and maintenance of body position on an inclined board were measured daily after injury to assess vestibulomotor function. Cognitive function was assessed on days 11-22 using the Morris water maze (MWM). Balance beam latency and inclined plane body position were reduced in both SI and SH rats (n = 20) (p < 0.05 vs. sham) (maximally at 24 h), and lasted 3-4 day postinjury; however, SH did not differ from SI. In the US group (n = 10), motor deficits were profound at 24 h (p < 0.05 vs. all other groups) and persisted for 10 days. The groups did not differ on grip test. In cognitive performance, there were no differences between sham, SI, and SH. US, however, produced significant cognitive dysfunction (vs. sham, SI, and SH), specifically, greater latencies to find the hidden platform through 22 days. Swim speeds were not significantly different between any of the injury groups and shams. These data indicate that (1) beam balance, inclined plane and MWM techniques are useful for assessing motor and cognitive function after TBI in immature rats; (2) SI produces motor but not cognitive deficits, which was not augmented by transient hypoxia; and (3) US created a marked but reversible motor deficit up to 10 days, and a sustained cognitive dysfunction for up to 22 days after TBI.
为了确定未成熟的斯普拉格-道利大鼠（17日龄）弥漫性重度创伤性脑损伤（TBI）后的运动和认知缺陷，使用一种新的闭合性颅脑重物坠落模型，将四组动物损伤至不同严重程度：（假手术组、重度损伤组[SI：100克/2米]、SH组[SI + 低氧血症（创伤后FiO₂为8%持续30分钟）]和超重度损伤组[US：150克/2米]）。损伤后每天测量平衡木上的潜伏期、握力测试表现以及在倾斜板上的身体姿势维持情况，以评估前庭运动功能。在第11 - 22天使用莫里斯水迷宫（MWM）评估认知功能。SI组和SH组（n = 20）的平衡木潜伏期和倾斜平面身体姿势均降低（与假手术组相比，p < 0.05）（在24小时时最大），并在损伤后持续3 - 4天；然而，SH组与SI组无差异。在US组（n = 10）中，24小时时运动缺陷严重（与所有其他组相比，p < 0.05），并持续10天。各组在握力测试方面无差异。在认知表现上，假手术组、SI组和SH组之间无差异。然而，US组产生了显著的认知功能障碍（与假手术组、SI组和SH组相比），具体而言，在22天内找到隐藏平台的潜伏期更长。任何损伤组与假手术组之间的游泳速度均无显著差异。这些数据表明：（1）平衡木、倾斜平面和MWM技术可用于评估未成熟大鼠TBI后的运动和认知功能；（2）SI导致运动缺陷但无认知缺陷，短暂缺氧并未加剧这种情况；（3）US造成了明显但可逆的运动缺陷，持续长达10天，以及TBI后长达22天的持续认知功能障碍。
