Effects Of Low Dose Radiation Pretreatment On Brain Radiation Injury

With the progress of nuclear medicine and space physiology, People become more and more interesting in the radiation injury and it's protection study. We have already investigated the mechanism of benzodiazepine(BZ) drugs and receptor in the brain radiation injury .This research selected low dose radiation(LDR) pretreatment as a physiatric method to protect the brain radiation injury. The experiments investigated the role of low dose radiation pretreatment under the acute brain radiation injury in the early stage on tissue and molecul level. In order to provide some useful data of brain radiation injury protection.Methods100mGy was selected as the pretreatment dosages. 25Gy was selectedas the challege dosages. Experiment rats were divided into three groupsrandomly, group one as simple group: the group irradiated with nopre-irradiation used; group two as 6h-group: the group irradiated with LDRpretreatment 6h before 25Gy irradiation; group three as 24h-group: thegroup irradiated with LDR pretreatment 24h before 25Gy irradiation. Theobservation was done 6 hours and 1 month after irradiation.1, The effect of the LDR pretreatment on the free radical after irradiated:Detected the effect of LDR pretreatment to the vigor of the superoxidedismutase ( SOD ) and the contents of malondialdehyde ( MDA ) afterthe brain tissue homogenate. 2> The effect of the LDR pretreatment on the Ca2+-ATPase after irradiated:Detected the effect of LDR pretreatment to the vigor of theCa2+-ATPase after the brain tissue homogenate. 3 > The effect of the LDR pretreatment on the neuron in the hippocampusregion after irradiated: Observe the changes of the pathomorphologywith the Hematoxylin-eosin (HE) staining, and the changes of nervecell number in the hippocampus region.ResultsK Compared with the simple group, The group with LDR pretreatment showed the increasing of SOD and the decreasing of MDA at 6 hours after 25Gy irradiation. In addition, there was no difference between the 6h-group and the 24h-group.2, Compared with the simple group, The 6h-group showed the higher increasing of Ca2+-ATPase vigor at 6 hours after 25Gy irradiation. But there was no difference between the 24h-group and the simple group.3> Compared with the simple group, The group of irradiated with LDR pretreatment showed the lighten neuron injury in the hippocampus region after irradiated. And there was no difference between the 6h-group and the 24h-group.4> LDR pretreatment has protection action in some degree to the brain irradiation injury, adaptation reaction has different influence to different index.ConclusionLDR pretreatment has protection action in some degree to the acute rat brain irradiation injury in some period in our observation. It could infer that the suitable LDR pretreatment play a protective role in the brainradiation injury.