Institute of Physiology, First Faculty of Medicine, Charles University in Prague, Prague, Czech Republic.
Physiol Res. 2013;62(Suppl 1):S75-80. doi: 10.33549/physiolres.932566.
Our previous experiments revealed that water intoxication and osmotic BBB disruption in the rat allow penetration of high-molecular substances into the brain and that resulting changes in the internal environment of the CNS lead to pathological development, such as the loss of integrity of myelin. The aim of the present study was to determine whether the previously described phenomena are associated with increased water content in the brain. To answer the question following methods were used: a) water intoxication: intraperitoneal administration of distilled water, b) osmotic BBB disruption: application of mannitol (20 %) selectively into the internal carotid artery, c) brain wet weight was measured after decapitation, and subsequently (after six days in thermostat set at 86 °C) the dry weight were estimated d) in animals with 20 % and 30 % hyperhydration the degree of myelin deterioration was estimated e) animal locomotor activity was tested by continuous behavior tracking and analysis. Brain water content after water intoxication and following the administration of mannitol was higher than in the control group. Different degrees of hyperhydration led to different levels of brain water content and to different degrees of myelin impairment. Hyperhydration corresponding to 20 % of the body weight brought about lower locomotor activity. Increased water content in the brain after the BBB osmotic disruption is surprising because this method is frequently used in the clinical practice.
我们之前的实验表明，水中毒和血脑屏障渗透在大鼠中会导致高浓度物质渗透进入大脑，而中枢神经系统内部环境的变化会导致病理性发展，如髓鞘完整性的丧失。本研究的目的是确定之前描述的现象是否与大脑含水量的增加有关。为了回答这个问题，我们采用了以下方法：a）水中毒：腹腔内给予蒸馏水，b）血脑屏障渗透：选择性将甘露醇（20%）应用于颈内动脉，c）断头后测量脑湿重，然后（在 86°C 的恒温器中放置六天后）估计脑干重，d）在 20%和 30%高水合的动物中，评估髓鞘退化的程度，e）通过连续行为跟踪和分析测试动物的运动活动。水中毒和甘露醇给药后大脑的含水量高于对照组。不同程度的高水合导致不同程度的脑含水量和不同程度的髓鞘损伤。与体重的 20%对应的高水合导致运动活动降低。血脑屏障渗透后大脑含水量的增加令人惊讶，因为这种方法在临床实践中经常使用。
