Investigation Of Stereostactic Control Of Fluid-percussion Impact In Traumatic Brain Injury Model In Rat

Objective: The perfect model of traumatic brain injury in animals is a base of research of mechanism of the traumatic brain injury and it's diagnosis and treatment. Now a serial of traumatic brain injury models is established in the world, especially the rat traumatic brain injury model, and it has become the most popular model for it's advantage of the gene sequence similar to human being;easy to culture and the convenient getting sample. But now the rat or other small animals traumatic brain injury models have some fault such as difficulty in fixing the wakened animals before hitting;difficulty in precisely controlling site (especially the site of control coup) of trauma;instability of hit force ... etc, and all these factors made the seldom error bigger in traumatic brain injury models in the small animals and this influences the experiment consult of small animal traumatic brain injury model directly. To avoid all these default we have mentioned above and stabilize the small animal traumatic brain injury model and improve the quantity of the experiment traumatic brain injury model in small animals;we used standardized operation and world wide used fluid-percussion impact traumatic brain injury instrument in our investigation and through designing, using small animal stereotatic apparatus;improving fluid-percussion connection system and optimizing experiment route we established a fluid-percussion traumatic brain injury model in small animals that have high precision, high stability, better repeat and easy in operating for our experiment. This made a fundamental base for more conventional animal experimentalresearch correlating with traumatic brain injury models.Methods: 1. Made small animal stereotactic control instrument: design thestereotactic fixing equipment which can fit all directions and can rotate adjustablely, this instrument can fix the animals tightly and can adjust the site precisely in it's wakened state. 2. Improve the fluid-percussion connection system: improve instrument which connects fluid-percussion traumatic instrument and small animals (rat) in the fluid-percussion traumatic brain injury model;design connecting system which has tight connection, can prolong moderate connection with little pressure attenuation, can be exhausted easily and can be operated easily. 3. Observation of the stereotactic control fluid-percussion impact in brain injury model: 92 adult rats were divided into two groups: experiment group (n =88) and control group (n=4). Experiment group is divided into 4 sub-groups, there are 22 rats in every group. The standard operating procedure was used in both experimental group and control group. For the control group we did not made fluid-percussion impact injury, the experiment made the rats into three types of traumatic brain injury models: mild, moderate and severe. The vital signs and scale of neurologic influences in behavior were studied in experimental animals. The characteristics of MRI inspect in the general samples and pathology slice were observed.Result : hi our experiment we have designed small animal stereotactic controlinstrument which can fit all directions and can rotate adjustablely. This instrument can fix the animals tightly and adjust the site precisely in it's wakened state. The improved fluid-percussion connection system connects tightly;can be prolonged moderately, has a slight pression attenuation, exhausts easily and operates easily. The traumatic brain injury models system above has the characteristics of precision of injury site, high stability of injury degree, better repeatability andlittle individual seldom error. The observation of the impact injured rats demonstrated that: the higher hit intensity brings the more severe injury, the high mortality, the lower behavior scale, the more distinctive contusion and it's MRI iconography change. These improvement can satisfy the necessity of more complicated investigations.Conclusion: There are some keys points for controlling the quality of smallanimal traumatic brain injury models, which include the stability of animal fixing, precise site of hit, the well control of hit direction, the better and tight and easy operating connection. With the help of the improved small animal fluid-percussion impact traumatic brain injury system we can repeat many clinic hackneyed traumatic brain injury models and this has made a fundamental base of animal experiment for more research of traumatic brain injury.