Hippocampus schizophrenia

Heckers, S. Neuroimaging studies of the hippocampus in schizophrenia. Hippocampus 11 520-528, 2001. 

Harrison PJ, Eastwood SL. 2001. Neuropathological studies of synaptic connectivity in the hippocampal formation in schizophrenia. Hippocampus 11 508-519. 

Medoff DR, Holcomb HH, Lahti AC, Tamminga CA. 2001. Probing the human hippocampus using rCBF Contrasts in schizophrenia. Hippocampus 11 543-550. 

Edgar PF et al. Comparative proteome analysis of the hippocampus implicates chromosome 6q in schizophrenia. Mol. Psychiatry 2000 5 85-90. 

Some intracellular signal transduction molecules are reduced in schizophrenia. The release of neurotransmitters is regulated by a family of proteins that coordinate vesicular trafficking (see Ch. 9). Of these, the expression of complexin I and II appears to be decreased in prefrontal cortex and subfields of the hippocampal formation, and the ratio of complexin I to complexin II is elevated in the hippocampus [35], SNAP-25 (Synaptosomal Associated Protein, kDa 25) has inconsistently been found to be down-regulated in both these regions. Synapsin expression is also reduced, but more robust decrements have been observed in bipolar disorder (Ch. 55). 

Serotonin 5-HT1A Human cDNA Alzheimer s disease, anxiety, depression, schizophrenia, hypertension, inflammation, pain, migraine, spasticity ulcers, obesity glaucoma Somatodendritic autoreceptor in hippocampus and raphe nuclei, circadian rhythm, somatodendritic heteroreceptor at cholinergic terminals of myenteric plexus... 

There are some indications that GABAergic axonal innervation is diminished in the cortex in schizophrenia. A deficit of GAD-immunoreactive puncta was reported in frontal cortex (Woo et al., 1998) and hippocampus (Todtenkopf Benes, 1998), while the cortical plexus of (GABAergic) parvalbumin-immunoreactive fibres is also diminished (Reynolds et al., 2001). The latter two studies reported a positive correlation of these measures of innervation with total antipsychotic drug exposure, indicative of protective or stimulatory effects of chronic drug treatment. 

Woo TU, Whitehead RE, Melchitzky DS, Jewis DA (1998) A subclass of prefrontal GABA axon terminals are selectively altered in schizophrenia. Proc Natl Acad Sci U S A 95 5341-5346 Zhang Y, Perez Velazquez JL, Tian GE, Wu CP, Skinner FK, Caslen PL, Zhang L (1998) Slow oscillations (< 1 Hz) mediated by GABAergic interneuronal networks in rat hippocampus. J Neurosci 18 9256-9268... 

A mutation in the reeler gene has recently been associated with autism (Keller et al., 2000). Mild abnormalities in cortical neuron migration and in reelin-containing cortical interneurons have been observed in the brains of schizophrenic subjects (Guidotti et ah, 2000). Therefore, a mutation in the reelin gene has also been implicated in schizophrenia. Changes in reelin have also been reported in the hippocampus in affective disorders (Eatemi et al., 2000). 

Fatemi, S.H., Earle, J.A., and McMenomy, T. (2000) Reduction in reelin immunoreactivity in hippocampus of subjects with schizophrenia, bipolar disorder and major depression. Mol Psychiatry 5 654-653. 

The dorsal and ventral hippocampus is involved in the formation of social memory (van Wimersma Greidanus and Maigret, 1996). Neonatal ablations of hippocampal regions can lead to decreased and abnormal social behavior in rhesus monkeys that is reminiscent of severe neuropsychiatric disorders in humans such as autism and schizophrenia (Bachevalier et ah, 1999). These monkeys are often withdrawn socially and will develop locomotoric stereotypies a pattern similar to that found in autistic children. 

In addition to an abnormality in the corticostriatal system, it is also possible that a disorder in the dopamine-glutamate system occurs in other subcortical regions which could account for some of the symptoms seen in schizophrenia. The hippocampus and the associated entorhinal cortex are important areas of the brain concerned in memory formation, information... 

Ohnuma T, Kato H, Arai H, Faull RL, McKenna PJ, Emson PC. Gene expression of PSD95 in prefrontal cortex and hippocampus in schizophrenia. Neuroreport 2000 11 3133-3137. 

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