Cornu Ammonis

Cells incorporating BrdU in CA1 were observed at all time-points, but their number was markedly increased in postischemic monkeys (Fig. 19). The BrdU+ cells were homogeneously dispersed throughout the layers of CA. In CA2-3, an increase— similar to CA1—of proliferating cells was observed. In the control animals, the density of BrdU+ cells was on average 10-20/mm2 and increased approximately 10 times after ischemia (Fig. 20). The postischemic monkeys had significantiy more Brdll+ cells on days 23 and 44 compared to the controls (Fig. 20), and even 

A Short-term group B Long-term group 

Control Ischemia Control Ischemia Control Ischemia Control Ischemia 

not available p 0.001, p 0.05 versus respective controls, Kruskal-Wallis, or Mann-Whitney tests 

In the long-term survival monkey group, microglia again represented the largest proportion of BrdU+ cells (Fig. 23A Table 5). In addition, a few 2/,3/-cyclic nucleotide 3 -phosphodiesterase (CNP)+ oligodendrocytes incorporated BrdU in the postischemic monkeys (Fig. 23B Table 5). In the control CA, we identified just 1-2 BrdU+/CNP+ cells representing about 0.5% of the BrdU+ cells. Thus, in the control monkeys most of the BrdU+ cells were of an unidentified phenotype. 

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The hippocampus, which got its name from the Greek word for seahorse, due to its form, is a nucleus in the depth of the temporal lobe. The hippocampus is important for the integration of sensory information, for spatial orientation and for memory formation. The hippocampal formation contains the CA (cornu ammonis) regions, the dentate gyms and the subiculum. 

FIGURE 26-5 Immunohistochemical localization of type I corticosteroid receptor (mineralocorticoid receptor) in the rat hippocampus. (A) Mineralocorticoid immunoreactivity is concentrated in pyramidal cell fields of the cornu ammonis (CA2). (B) High-power photomicrograph shows that steroid-bound mineralocorticoid receptors are primarily localized to neuronal cell nuclei. (Courtesy of Dr James P. Herman, Department of Anatomy and Neurobiology, University of Kentucky.)... 

Figure 3. Distribution of histamine-immunoreactive nerve fibers in normal human hippocampal structures. F, fimbriae CA1-CA3, cornu ammonis, areas 1-3 GD, gyrus dentatus S, subilucum PHG, parahippocampal gyrus. From Panula et al.42...

Fig. 19 Staining for BrdU in CA1 of short-term (A) and long-term (B) monkey groups. Note the marked increase of positive cells after ischemia and their homogeneous distribution between pyramidal and radiate cell layers. A monkey not injected with BrdU served as a negative control (-). The position of the visual field within cornu Ammonis corresponds to the middle portion of CA1 as shown in Fig. 3A). Scale bar= 100 pm...

Fig. 20A, B Statistical analysis of the density of BrdU+ cells in cornu Ammonis. A In the short-term survival group after BrdU the density peaked in the second postischemic week (days 9 and 15). B In long-term monkey group the density was significantly higher in postischemic compared to control brains. p< 0.05, p<0.01, p< 0.001, one-way AN OVA followed by Tukey-Kramer post hoc...

Fig. 23A-E (on page 41) Long-term fate of BrdU+ cells in cornu Ammonis (for all images, BrdU is shown in the left panel). A Rod-shaped Ibal+ microglia express BrdU in postischemic day-79 CA1 (arrows). B A few oligodendrocytes positive for CNP also colabeled with BrdU in the postischemic monkeys (micrograph from day-79 CA1). C Lack of colabeling of BrdU (arrows) with /3111-tubulin (day-44 CA1). D Lack of colabeling of BrdU (arrowheads) with NeuN (arrows) (day-44 CA1). E A cell that is positive for BrdU and Hu in CA4 (postischemic day 23) is depicted by arrows and shown in channel separation and orthogonal projections in the lower panel. Scale bars = 10 pm (A, B, E) 20 pm (C) 50 pm (D)...

Table 11 Approximate proportions of various de novo-generated cell phenotypes in several regions of adult monkey forebrain after ischemia (long-term survival animals). Note that outside the germinative centers DG and SVZa, the most common proliferating cells were microglial cells followedby astrocytes. BrdU+/Musashil+/GFAP cells in parenchyma were considered putative local progenitors (see text for details). Note that such cells were absent in cornu Ammonis...

Cornu Ammonis 80%—Microglia 15%—Astrocytes 3%—Oligodendrocytes 2%—Other... 

Brain-derived neurotropic factor Basic fibroblast growth factor Bromodeoxyuridine Cornu Ammonis... 

Unusually high levels of dysbindin-1 are found in neuronal and neuropil components of this brain area, which consists of the dentate gyrus (DG), hippocampus proper (i.e., cornu ammonis [CA] fields 1-3]), and the subiculum ( Figures 2.2-13c—d and O 2.2-14V). As in the case of the basal ganglia, an anatomical introduction clarifies the functional implications of dysbindin-1 found in the hippocampal formation ( Figures 2.2-13-2.2-18). For a detailed review of its anatomy, see Amaral and Lavenex (2007). 

Most studies of overall cell density have reported no significant change in schizophrenia (Dwork, 1997 Harrison, 1999 Arnold, 2000). Two studies provided estimates of total hippocampal cell number and found no changes in any of the four sectors of the cornu ammonis in schizophrenia (Heckers et al., 1991 Walker et al., 2002). The finding of normal total cell number is important for the interpretation of decreased hippocampal volume reported by neuroimaging studies of patients with schizophrenia. In contrast to neuropsychiatric disorder such as temporal lobe epilepsy and dementia, smaller hippocampal volume is not the macroscopic correlate of pyramidal cell loss in schizophrenia. 

CCAAT box/ enhancer binding protein complement C3 fragment d complement C4 fragment d cornu ammonis... 

Figure 6.1. Schematic drawing by Ramon y Cajal (1911) of tire main cells, connections and flow of impulse traffic in tlie hippocampus. Alv alvus, CA Cornu Ammonis, DG dentate gyi us, EC entorhinal cortex, MF mossy fibers, PP perforant patli, Sch C ffer collaterals. Sub subiculum...

Abbreviations Al = primary auditory area ac = anterior commissure Acc = accumbens nucleus AON = anterior olfactory nucleus BF = barrel field BLA = basolateral nucleus of the amygdala CAl = cornu ammonis 1 CA3 = cornu ammonis 3 cc = corpus callosum Cg = cingulate area CPu = caudate-putamen DCb = deep cerebellar nuclei DCo = dorsal cochlear nucleus DG = dentate gyrus DMV = dorsal motor nucleus of the vagus nerve ECu = external cuneate nucleus EP = external plexiform layer ER = entorhinal cortex f = fornix Fa = facial nucleus fa = facial nerve fr = fasciculus retroflexus G1 = glomerular layer GPe = (external segment of the)... 

Somatostatin-containing perikarya have been reported in the fascia dentata, the cornu Ammonis, and the subiculum (Finley et al. 1981, Shiosaka et al. 1982). The lower cortical layers, the CAl region of the hippocampus, and the habenula are highly enriched in [ l-Tyr ]SS receptor sites, the dentate gyrus has an intermediate density, whereas the hypothalamic region is almost devoid of receptor sites (Maurer and Reubi 1985). 

Beta-site amyloid precursor protein [APP]-cleaving enzyme Brain-derived neurotrophic factor Cornu ammonis... 

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