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

本研究在人的神经核内发现了许多芳香族L-氨基酸脱羧酶阳性、酪氨酸羟化酶阴性和色氨酸羟化酶阴性的D-神经元。精神分裂症患者海马齿状回内、中分子层内D-神经元数目显著低于对照组（P<0.05，t检验），凝集素染色发现海马齿状回内、中分子层内有直径3-10μ的球形沉积物（SPD）。精神分裂症患者的SPD数高于老年人和退行性痴呆患者。ACC接受来自海马、前扣带皮层、杏仁核和丘脑的兴奋性氨基酸纤维投射，并向腹侧钯和中脑投射。ACC被认为是将情绪转换为行动的界面，并与精神分裂症的病因学有关。突触通路位于齿状回颗粒细胞产生的齿状回外部。这对着大约三分之二的颗粒细胞树突，并且在这一区域结束的突触终末中有80-85%是突触终末。相比之下，分子层的内部三分之一部分接收来自CA 4区和隔的传入。在齿状回的分子层中存在许多SPD表明，这些沉积物和海马CA 4区神经元树突之间可能存在不利的相互作用，并且可能在精神分裂症和/或退行性痴呆患者的记忆干扰中起关键作用。关于海马结构，精神分裂症可能的海马病因学的假说已经制定。本研究提示，海马齿状回ACC和SPD内的D神经元可能与精神分裂症的病理有关。

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.