Study On The Regularity Of Iron Deposition In Brain Induced By Iron Overload In Rat Model

Object By establishing a rat model of brain iron deposition induced by iron overload,the regularity of brain iron deposition in different regions was discussed.The relationship between iron content and SWI,T2 value and T2~*value was studied by comparing with pathology,and the advantages or disadvantages of quantitative cerebral iron deposition in each sequence were compared.To investigate the relationship between brain iron content,liver iron content and serum transferrin.Whether the brain iron content of normal control group and experimental group is symmetrical or not.MATERIALS AND METHODS 20 SD rats,male,weight 368-455g,were divided into 6 rats in the control group and 10 rats in the experimental group.Rats in the control group were given MRI(head SWI,T2~*,T2 and liver R2~*)after anesthesia without special treatment,and the sequence signal values of cerebral cortex,striatum,thalamus,brainstem,hippocampus and liver R2~*were measured.the next day morning,blood was drawn by excessive anesthesiaand to examineSerum ferritin,brain and liver tissues were taken for Prussian blue staining and actual iron content.The experimental group was injected with iron once every 3 days,and 2 rats were randomly selected for MRI scan and value test each time after 3 days.RESULTS T2 in the left and right striatum of rats in the control group was P=0.036,and the rest parts and sequence P values were>0.05.Comparison of left and right cortical SWI in the experimental group P=0.025,and the rest regions and sequence P values were all>0.05.The cortex,striatum,thalamus sequences and brain stem compared with control group and the experimental group T2~*P<0.05,brainstem SWI and T2,hippocampus SWI,T2~*and T2compared with the control group P>0.05.No correlation was found between brain MRI signal value and actual brain iron content.The cortex,striatum,thalamus SWI,T2~*,brain stem T2~*,and hippocampal T2 were correlated with the total amount of iron injection,and the absolute values of r were between0.565 and 0.791.There was a correlation between cortex,striatum,thalamus SWI,brain stem T2~*,hippocampus T2 and liver R2~*,and the correlation coefficient r was 0.713,0.652,0.673,-0.661 and-0.611..There was a correlation between the actual iron content in the brain and liver(r=0.929).CONCLUSIONS The T2 value of normal striatum and SWI value of iron deposited rat cortex was asymmetrical,the rest parts and sequences were symmetrical.In the experimental group,the sequences of cortex,striatum,thalamus and brain stem T2~*showed iron deposition,while no iron deposition was found in brain stem SWI and T2,hippocampal SWI,T2~*and T2.There was a correlation between the brain MRI signal value and the total amount of iron injection and liver R2~*value in rats with iron deposition.The actual liver iron content was highly correlated with the actual brain iron content.No correlation was found between brain MRI signal value and actual brain iron content.