Study On The Effects Of Spinal Manipulation On The Late-onset Behavior Of Rats With Hypoxic-ischemic Encephalopathy And Its Mechanism

Object:The study was to investigate the effects of spinal manipulation on the late-onsetbehavior (including locomotor activity, anxiety-like behavior and cognitive function)of rats with hypoxic-ischemic encephalopathy (HIE) and its inflammatory regulatedmechanism.Methods:72new born SD rats with three days-postnatal were randomly divided intocontrol group (n=24), model group (n=24) and massage group (n=24). The HIE modelwas established by total unilateral carotid artery ligation combined with hypoxia. Thepups in the massage group were undergone the spinal massage intervention for20days, one time every day,20min each time. The model and control groups with notreatment were placed in the same temperature and humidity environment. All ratswere given the same feeding practice.The locomotor activity, the anxiety-like behavior and the cognitive function ofrats in each groups were evaluated by Using Elevated Zero Maze (EZM), Open FieldTest (OFT) and Morris Water Maze (MWM), respectively．The levels of IL-1β andTNF-α protein in the rats serum were detected by Suspension Array.Results:1. Compared with the model group, the EZM closed arm residence time of pupswas significantly increased and the reducing the dwell time open arms of pups wassignificantly decreased in the massage group (P<0.05), which indicated that spinalmanipulation reduced anxiety-like behavior of rats with HIE. 2. Compared with the model group, the upright number of open-fieldexperiments, the activity total distance and fringe travel time of pups weresignificantly decreased, but the total rest time of pups was significantly increased inthe massage group (P＜0.01, P＜0.05), which showed that spinal manipulationreduced the spontaneous activity of the rats with HIE.3. Compared with the model group, in massage group, Morris water maze test intraining2-3days the latency and swimming training distance of pups weresignificantly decreased (P＜0.01, P＜0.05), and the test latency of space explorationexperiments was significantly reduced. However, the distance to the platformquadrant was significantly increased. These results showed that spinal manipulationcan improve learning and memory of the rats with HIE.4. Compared with the model group, the protein expression levels of IL-1β andTNF-α in the serum of the rats in the massage group were significantly decreased (P＜0.05), which indicated that spinal manipulation can reduce the protein expression ofIL-1β and TNF-α in serum of the rats with HIE.Conclusion:spinal manipulation can improve long-term anxiety-like behavior，locomotoractivity and cognitive function defects of HIE rats. The mechanism may be relatedwith that spinal manipulation down-regulates the inflammation of the rats with HIE.