A research for molecular level characteristics of monoaminergic neurons in schizophrenia by means of histochemical approach on autopsied human brains

点击翻译按钮获取中文摘要

In this study, we found many Aromatic L-amino acid decarboxylase positive, tyrosine hydroxylase negative and tryptophan hydroxylase negative neurons (D-neurons) in the nucleus (Acc) of human. The number of D-neurons in schizophrenic patients was significantly lower than in controls (p<0.05, t-test) in the Acc. And, we found the spherical deposits (SPDs) with a size of 3-10μ in diameter mainly within the inner and middle molecular layer of the dentate gyrus of hippocampal formation by lectin staining. The number of the SPDs in schizophrenic patients was higher than in aged individuals and degenerative dementia patients. The Acc receives fiber projections of excitatory amino acid from the hippocampus, anterior cingulate cortex, amygdala and thalamus, and the nucleus projects to ventral palladium and midbrain. The Acc is thought to be an interface that converts emotion to action and to relate to the etiology of schizophrenia. The perforate pathway synapses on the outer portion of the dentate that arises from the dentate gyrus granule cells. This subtends approximately two-thirds of the granule cell dendrites and the perforate pathway contributes 80-85% of the synaptic terminals that end in this zone. By contrast, the inner one-third portion of the molecular layer receives afferents from the CA4 zone and from the septum. The presence of many SPDs in the molecular layer of the dentate gyrus suggests that there may exist a disadvantageous interaction between these deposits and dendrites of neurons of the CA4 zone of the hippocampus and may play a key part in the perturbation of the memory of patients with schizophrenia and/or degenerative dementias. Concerning the hippocampal formation, hypotheses of a possible hippocampal etiology of schizophrenia have been formulated. This study suggests that D-neurons in the Acc and SPDs in the dentate gyrus of hippocampal formation may relate to the pathology of schizophrenia.