Comparative Study Of Pathological Changes In Different Parts Of Schizophrenic Brain Tissue

Objective:Schizophrenia plays an important role in forensic psychiatric identification. But its etiology is unknown, and the pathogenesis is unclear too. The lack of objective laboratory diagnostic indicators made it difficult for forensic workers to identify it. Imaging studies find that schizophrenia patients have many parts abnormal in cortical and subcortical structures, but the relationship between those changes and schizophrenia is not clear. Because of the unique of the schizophrenic human brain, pathology reports were rare, and there were scattered case studies abroad, the results were vary. Our experimental group collected 13 cases of schizophrenia brain tissue by autopsy,which were diagnosed schizophrenia by CCMD-3 criteria for clinical (7 males, 6 females). We did systematic neuropathological study and stereological analysis to show pathological changes in different parts of schizophrenia brain. This experiment tried to explore the etiology and pathogenesis of schizophrenia; while the clinical diagnosis and forensic identification about schizophrenia can get reference too.Method: 1, Experimental materials and groups: Based on completely randomized design for single factor, brain tissue samples were divided into schizophrenic group(be diagnosed schizophrenia by CCMD-3 criteria for clinical)and control group( be completely no mental illness, nervous system, brain disease and traumatic brain injury history).2, Experimental method:(1) Overall morphology: by visual observation; quality weighing; volume measurement; cerebral cortex thickness measurement, we try to find the overall morphological changes and differences existing in the schizophrenic group.(2) Histopathological study: Various parts of brain tissue (frontal lobe, parietal lobe, temporal lobe, occipital lobe, insula, limbic lobe, hippocampal formation, olfactory brain, fiber links, basal ganglia between the brain, brain stem, cerebellum and other parts) were harvested, made into paraffin section, HE staining and silver staining; for microscopy and finding pathological changes existed in schizophrenia group.(3) Stereological analysis: Biopsy of pathological changes were analyzed by stereological methods.(4) Trace elements detection: Over parts of brain tissue (frontal lobe, hippocampus, back thalamus, brain stem, cerebellum) were harvested, concentrated nitric acid digestion, atomic absorption spectrometry assay, and analyzed the content of trace elements (Fe, Zn) with the control group. 3, Statistical analysis: All data used SPSS 13.0 statistical package, did description, analysis of variance, and two sets of tests which were designed completely randomized for single factor (LSD method). P <0.05 indicated significant difference.Results:1, Results of the overall morphological study: Compared with the control group, schizophrenia brain shriveled (obviously in the frontal, temporal and occipital lobe). Quality reduced (males reduced 11.57%, females reduced 10.93%), volume became smaller (males reduced 12.20%, females reduced 14.53%), and cerebral cortical was thinner (males reduced 9.14%, females reduced 14.88%) (P <0.01)2, Schizophrenia histopathological findings:(1)Frontal lobe (prefrontal, posterior frontal gyrus, medial frontal gyrus) nerve nucleus condensation, degeneration, necrosis, satellite phenomenon and the phenomenon of perineural increasing, proliferation of glial cells, capillary dilatation and congestion, density increased, and a large number of amyloid corpuscles formed. (2) Hippocampal (hippocampus, dentate gyrus) have part of the nerve cell nucleus condensation and degeneration, white matter loose edema, and a large number of senile plaques formed. (3)Synapses ball of olfactory bulb away, nerve cells decreased in gray matter layer, with glial cells proliferation, and a large number of amyloid corpuscles formed.3, Trace elements test results: Fe was decreased in frontal lobe of schizophrenic brain, and hippocampal had both Fe decreased and Zn increased.Conclusion:1, Schizophrenia brain shriveled. The quality and volume was significantly reduced, compared with the control group, cerebral cortical was thinner.2, Frontal cortex and hippocampal pathological changes (nerve nucleus condensation, degeneration, necrosis, capillary dilatation and congestion, density increases, the satellite phenomenon and the phenomenon of perineural increased, proliferation of glial cells, a large number of amyloid corpuscles formed (frontal lobe), a large number of senile plaques formed (hippocampus) )may be the key reason causing schizophrenia. Pathological changes in olfactory bulb and olfactory tract (synaptic ball of olfactory bulb disappeared, reduced nerve cells of gray matter layer, with glial cells proliferation, and a large number of amyloid corpuscles formed) may affect the sense of smell in schizophrenia group.3, The lower content of Fe in frontal cortex and hippocampal may be the risk factor which caused neuropathological changes of corresponding parts and ultimately lead to schizophrenia.