The Effect Of ⁶⁰Co-γ Radiation On The Auditory Pathway Of Mice

Objective:After the mice awake cerebral radiation model was established, a fluorogold (FG) retrograde tracing technique was used to study the effect of radiation brain injury on the auditory pathway and the change of neurons,which provided the theoretical basis to the study on radiation auditory injury.Methods: Thirty adult mice were used in our experiment with weight of (25-30)g, regardless gender, which were divided into normal control group and 30gy-irradiated group which were feeding 8 weeks. Put the mice in stereotaxic apparatus , a microglasstube containing fluorogold was inserted into the mice brain , then using microelectrie current introduce fluorogold into the claustrum to examine the auditory pathway ,that is , the chang and the distribution of the neurons. Result: 1.Compared with the control group, large dose irradiated group mice's spatial memory ability were decreased. 2.Compared with the control group, 1 month after irradiation, the olifodendroglial cell of the irradiated group became worse: nuclear pyknosis, capillary endothelial fracture, tight junctions between endothelial cells destroyed. 3.The distribution of FG—labeled neurons was observed under fluorescent microscope. At the contralateralof surgical site, it was found that the FG—labeled neurons were mainly distributed in the area of dosal tegmental nucleus,pericentral part(DTgP),laterodors-al tegmental nucleus,wentral part(LDTgV),central nucleus of the lateral unferior colliculus(CIC),lateral superior olive(LSO),medial superior olive(MSO), olivocochlear bundle(ocb).At the surgical site ,it was found that the FG—nucleus of the trapezoidbody(Tz),ventral cochlear nucleus,anterIor part(VCA), and superficial flial zone of the cochlear nuclei(SGI).4. It was found that the FG—labeled neurons were mainly distributed in the area of DTgP,LDTg,LDTgV,CIC,LSO,MSO,CAI,Tz,ocb and SGI.Corresponding to this,there was difference on the morphology of the neurons to the normal group.5. Compared with the control group, the number of FG—nucleus,density in the three grades neurons about irradiated group mice were increased significantly(P<0.01). 6. Compared with the control group,the area of FG—nucleus,distribution density in the three grades neurons about irradiated group mice were increased significantly (P<0.01). Conclusion: 1. There was precise distribution of the three grades nervon of the Ruditory pathway in mice. 2. There was varying degrees of damage to each grade neurons of auditory pathway.