Flood impact on the Spanish Mediterranean coast since 1960 based on the prevailing synoptic patterns.

In a changing climate and in social context, tools and databases with high spatiotemporal resolution are needed for increasing the knowledge on the relationship between meteorological events and flood impacts; hence, analysis of high-resolution spatiotemporal databases with detailed information on the frequency, intensity, and impact of floods is necessary. However, the methodological nature of flood databases hinders relating specific flood events to the weather events that cause them; hence, methodologies for classifying flood cases according to the synoptic patterns that generate them are also necessary. Knowing which synoptic patterns are likely to generate risk situations allows for a probabilistic approach with high spatial resolution regarding the timing of occurrence, affected area, and expected damage from floods. To achieve these objectives, we use the SMC-Flood Database, a high-resolution spatiotemporal flood database covering the 1960-2015 period for all municipalities along the Spanish Mediterranean coast. To relate floods with the synoptic conditions that generated them, we used a multivariate analysis method on the corrected daily anomalies of the surface pressure fields, 850 hPa temperature, and 500 hPa geopotential height, all of which were obtained from the 20th Century Reanalysis Project V2. Results show that 12 atmospheric synoptic patterns can statistically explain the 3608 flood cases that occurred in the study area between 1960 and 2015. These flood cases were classified into 847 atmospherically induced flood events. These results reduce the uncertainty during decision making because of the classification of potential risk situations. The Mediterranean Basin is a region where floods have serious socioeconomic impacts; hence, this work helps improving prevention measures and providing information for policymakers, mainly regarding land use planning and early warning systems.

Multi-Pulse Excitation for Underwater Analysis of Copper-Based Alloys Using a Novel Remote Laser-Induced Breakdown Spectroscopy (LIBS) System.

In this work, the use of multi-pulse excitation has been evaluated as an effective solution to mitigate the preferential ablation of the most volatile elements, namely Sn, Pb, and Zn, observed during laser-induced breakdown spectroscopy (LIBS) analysis of copper-based alloys. The novel remote LIBS prototype used in this experiments featured both single-pulse (SP-LIBS) and multi-pulse excitation (MP-LIBS). The remote instrument is capable of performing chemical analysis of submersed materials up to a depth of 50 m. Laser-induced breakdown spectroscopy analysis was performed at air pressure settings simulating the conditions during a real subsea analysis. A set of five certified bronze standards with variable concentration of Cu, As, Sn, Pb, and Zn were used. In SP-LIBS, signal emission is strongly sensitive to ambient pressure. In this case, fractionation effect was observed. Multi-pulse excitation circumvents the effect of pressure over the quantitative analysis, thus avoiding the fractionation phenomena observed in single pulse LIBS. The use of copper as internal standard minimizes matrix effects and discrepancies due to variation in ablated mass.

Elemental analysis of materials in an underwater archeological shipwreck using a novel remote laser-induced breakdown spectroscopy system.

LIBS analysis of submerged materials in an underwater archeological site has been performed for the first time. A fiber-optics-based remote instrument was designed for the recognition and identification of archeological assets in the wreck of the Bucentaure (Bay of Cadiz, South of Spain). The LIBS prototype featured both single-pulse (SP-LIBS) and multi-pulse excitation (MP-LIBS). The use of multi-pulse excitation allowed an increased laser beam energy (up to 95 mJ) transmitted through the optical fiber. This excitation mode results in an improved performance of the equipment in terms of extended range of analysis (to a depth of 50 m) and a broader variety of samples to be analyzed (i.e., rocks, marble, ceramics and concrete). Compared to single-pulse, an intensity enhancement factor of 15× was observed at the same irradiance value, 1.89 GW/cm(2). Thus, a longer pulse duration promotes the heating and melting of the sample, resulting in a greater mass ablated. As a consequence of the optimization of experimental conditions performed in laboratory, underwater characterization of ancient pottery was achieved.

Effect of pulse duration in multi-pulse excitation of silicon in laser-induced breakdown spectroscopy (LIBS).

The aim of this study is to investigate the mechanisms responsible for the increase in ablated mass and signal enhancement observed on multi-pulse excitation. Several experiments were designed to obtain evidence that confirms the laser-sample and/or laser-plasma interaction, with special attention to the role of the pulse width on these effects. A train of pulses, with a separation of a few microseconds between pulses, was used for laser-induced breakdown spectroscopy (LIBS) analysis. The signal emission of Si was improved by an enhancement factor of about 60 compared to conventional single-pulse LIBS (SP-LIBS). The number of spikes, their amplitude, and their pulse duration were found to be variable for different Q-switch delays. A temporal study was performed to determine whether or not a laser-plasma interaction took place. The effect of pulse width (as responsible of laser-sample interaction) was also evaluated. The results demonstrate that, although both interactions contribute to the observed effect, the process is predominantly governed by the pulse width.

Males but not females show differences in calbindin immunoreactivity in the dorsal thalamus of the mouse model of fragile X syndrome.

Fragile X syndrome (FXS), the most common form of inherited mental retardation, is caused by the loss of the Fmr1 gene product, fragile X mental retardation protein. Here we analyze the immunohistochemical expression of calcium-binding proteins in the dorsal thalamus of Fmr1 knockout mice of both sexes and compare it with that of wildtype littermates. The spatial distribution pattern of calbindin-immunoreactive cells in the dorsal thalamus was similar in wildtype and knockout mice but there was a notable reduction in calbindin-immunoreactive cells in midline/intralaminar/posterior dorsal thalamic nuclei of male Fmr1 knockout mice. We counted the number of calbindin-immunoreactive cells in 18 distinct nuclei of the dorsal thalamus. Knockout male mice showed a significant reduction in calbindin-immunoreactive cells (range: 36-67% lower), whereas female knockout mice did not show significant differences (in any dorsal thalamic nucleus) when compared with their wildtype littermates. No variation in the calretinin expression pattern was observed throughout the dorsal thalamus. The number of calretinin-immunoreactive cells was similar for all experimental groups as well. Parvalbumin immunoreactivity was restricted to fibers and neuropil in the analyzed dorsal thalamic nuclei, and presented no differences between genotypes. Midline/intralaminar/posterior dorsal thalamic nuclei are involved in forebrain circuits related to memory, nociception, social fear, and auditory sensory integration; therefore, we suggest that downregulation of calbindin protein expression in the dorsal thalamus of male knockout mice should be taken into account when analyzing behavioral studies in the mouse model of FXS.

Phenotypic changes in calbindin D28K immunoreactivity in the hippocampus of Fmr1 knockout mice.

Fragile X syndrome (FXS), the most prevalent form of inherited mental retardation, is caused by the lack of FMRP (fragile mental retardation protein) as a result of the transcriptional silencing of the FMR1 gene. Here we analyze the immunohistochemical expression of the calbindin D28K protein in the hippocampus of Fmr1 knockout (KO) mice and compare it with that of their wildtype (WT) littermates. The spatial distribution pattern of calbindin-immunoreactive cells in the hippocampus was similar in WT and KO mice but for each age studied (ranging from 3.5-8 months) the dentate gyrus of Fmr1-KO mice showed a significant reduction in calbindin-immunoreactive granule cells. Also, the number of calbindin-immunoreactive cells was reduced in the CA1 pyramidal layer in KO mice compared to their WT littermates. In addition, Frm1-KO mice showed a group of calbindin-immunoreactive cells located only in the left CA3b subregion that was only sometimes observed in WT mice. Overall, the absence of FMRP results in a dysregulation of the calbindin protein expression in the hippocampus. This dysregulation is cell type- and time-dependent and as a consequence key elements of the hippocampal trisynaptic circuitry may lack calbindin in critical periods for normal memory/learning abilities to be achieved and may explain some of the FXS symptoms observed in the Fmr1-KO mouse model.

Patterns of GABA and GABA Transporter-1 immunoreactivities in the developing and adult mouse brain amygdala.

We used immunohistochemistry to analyze the spatiotemporal patterns of GABA and GABA Transporter-1 (GAT1) immunoreactivities in the developing and adult mouse amygdala. GABA-immunoreactive(ir) neurons were first observed in the mouse amygdala at the embryonic day 15.5 (E15.5), and they became abundant throughout the amygdala perinatally. GAT1 immunoreactivity started to be observed in the mouse amygdala at E18.5. As development proceeds, GAT1 immunoreactivity was more intense, reaching a high density in some amygdalar nuclei at the second postnatal week. In general, GAT1-ir terminals were denser in pallial amygdalar derivatives, such as the basolateral complex than in subpallial derivatives, such as the central nucleus. Distinctive patterns of GABA and GAT1 immunoreactivities distinguish the basolateral complex and the central nucleus during postnatal development and in the adult. GAT1 immunoreactivity appears earlier in the basolateral complex than in the central nucleus. Moreover, the distribution of GAT1-ir fibers and terminals in the basolateral complex parallels the distribution of GABA-ir neurons whereas in the central nucleus the distribution of GAT1-ir terminals was not related with the amount of GABA-ir neurons, especially during development. Another major difference between the basolateral complex and the central nucleus was related to axonal specializations termed here as GAT1 cartridges. Our results indicate that GAT1-ir cartridges were numerous in the basolateral complex but they were completely absent in the central amygdala. Finally, we discuss the patterns of GABA and GAT1 immunoreactivities in relation with the different origin or cellular composition of the basolateral complex and central nucleus.

Expression of somatostatin and neuropeptide Y in the embryonic, postnatal, and adult mouse amygdalar complex.

Recent developmental studies indicate that distinct neuronal subpopulations in the amygdala, including somatostatin (SOM)-containing neurons, originate from progenitor domains in the anterior entopeduncular area, thus suggesting a different origin from subpallial territories for amygdalar versus cortical SOM-expressing interneurons, the latter derived from the dorsal part of the medial ganglionic eminence. In this context, we carried out an immunohistochemical study analyzing spatiotemporal expression patterns for SOM- and neuropeptide Y (NPY)-containing neurons in the embryonic, postnatal, and adult mouse amygdala. Our results indicate that SOM- and NPY-immunoreactive cells are present in the amygdalar complex from embryonic day (E)12.5, and that these peptidergic cells seem to arise from the anterior entopeduncular area progenitor domain. From E12.5 on there was a notable increase in the number and immunoreactivity of cells containing these peptides in distinct territories of the amygdalar complex, reaching a peak around birth. The distribution pattern for NPY neurons was very similar to that of SOM neurons in most nuclei of the amygdala, although the number of NPY neurons was always lower than that of SOM. At postnatal ages a reduction in the number of immunoreactive cells is observed in most amygdalar nuclei, remaining then similar from P14 to the adult. We interpret this reduction of the number of immunoreactive neurons in relation to the increased immunoreactivity for axons that occurs postnatally. We also suggest that the anterior entopeduncular area-derived SOM- and NPY-containing neurons in pallial and subpallial amygdaloid nuclei become local interneurons and projection neurons, respectively.

Efferent retinal projections visualized by immunohistochemical detection of the estrogen-related receptor beta in the postnatal and adult mouse brain.

Recently, a new nuclear receptor subfamily has been identified and referred to as estrogen-related receptors. This new group shares sequence similarity, target genes, co-regulatory proteins, and action sites with the estrogen receptors; however, natural estrogens are not estrogen-related receptors ligands. One of the receptors belonging to this group, estrogen-related receptor beta (ERRbeta), is essential for embryo development and is believed to be involved in estrogen-regulated pathways. In this study, we analyzed the presence of the ERRbeta protein in the mouse brain by means of immunohistochemistry, using a commercial polyclonal antibody against ERRbeta (Sigma, E0156). This study represents the first description dealing with the immunolocalization of ERRbeta in a mammalian brain. Our results revealed numerous ERRbeta immunoreactive fibers in the retinal efferent projections in the brain, which was in agreement with the presence of intense ERRbeta immunoreactivity in the cell bodies and axonal processes of the retinal ganglion cells. In both postnatal and adult brains, ERRbeta immunoreactive fibers were distributed in a pattern which perfectly matched the retinal efferent projections: optic tract, supraoptic commissure, hypothalamic suprachiasmatic nucleus, ventral and dorsal geniculate nuclei, pretectal nuclei, and superior colliculus. Due to reliable, fine, and complete staining of the retinal axons obtained with the anti-ERRbeta antibody (E0156), we suggest that this antibody could be used as a valuable tool for labeling the full retinofugal projections in postnatal or adult brains.

Distinct immunohistochemically defined areas in the medial amygdala in the developing and adult mouse.

The medial amygdala has been considered a subpallial structure, but various studies have shown that is a somewhat complex structure expressing both pallial and subpallial gene markers. In this regard, we analyzed the immunohistochemical expression of the neurotransmitter GABA, the vesicular glutamate transporter type 2 (VGLUT2), the neuronal nitric oxide synthase (nNOS), and the calcium-binding proteins calbindin-D28k (CB) and calretinin (CR) in the developing and adult mouse medial amygdala. From intermediate embryonic stages on, neurochemical data show a distinctive superficial region forming a band all along the medial amygdalar surface. This superficial band displays a strong VGLUT2-immunoreactive neuropil and numerous CR-immunoreactive fibers, as well as some nNOS-, CR- or CB-positive cells. In contrast, the superficial region of the posterior medial amygdala appears to be non-GABA immunoreactive. This band in the posterior medial amygdala matches a Tbr1-expressing territory. Our results also show differences between dorsal and ventral parts of the postnatal and adult posterior medial amygdala. Especially, a compact cell aggregate of nNOS immunoreactive cells was found in the ventral portion of the medial amygdala, whereas the dorsal part is occupied by scattered weakly stained cells. Comparison of our results with gene expression patterns and fiber-tracing studies, let us to propose that the superficial band is a pallial derivative, whereas the dorsal and ventral nuclei of the posterior medial amygdala receive each neurons from different subpallial compartments, and the latter one a subset of excitatory, pallial projection neurons.

Development and adult organization of the lateral part of the bed nucleus of the stria terminalis in the chicken.

The lateral part of the bed nucleus of the stria terminalis (BSTL) is a component of the subpallial amygdala located near the ventral sulcus of the lateral ventricle, but its limits have not been well defined in birds. In this study, we analyzed the expression patterns of a number of neurochemical markers: GABA, calbindin (CB), calretinin (CR), or neuronal nitric oxide synthase (nNOS), in the embryonic and adult chicken brain, to further characterize the organization of the avian BSTL. From embryonic day 16, it was possible to distinguish three different regions within BSTL on the basis of cytoarchitectonic and immunohistochemical features. A central region, referred to as lateral bed nucleus of the stria terminalis pars densocellularis (BSTLdc), is characterized by numerous tightly packed cell bodies, most of which are GABA-immunoreactive (ir), and two peripheral regions with lower cellular density displaying a moderate GABA expression, referred to as lateral bed nucleus of the stria terminalis, plexiform part 1 (BSTLp1) and plexiform part 2 (BSTLp2), respectively. In contrast to BSTLdc, both plexiform parts are characterized by the presence of many fibers and terminals immunoreactive for nNOS and CR, as well as some CR-ir scattered cells. A distinctive feature of BSTLp2 is a population of CB-ir cells embedded in a slightly CB-ir neuropil. Comparison of our immunohistochemical data with gene expression data suggests that BSTLdc and BSTLp1 are pallidal in nature, whereas BSTLp2 receives important contributions from the entopeduncular/preoptic area.

Dynamic patterns of colocalization of calbindin, parvalbumin and GABA in subpopulations of mouse basolateral amygdalar cells during development.

Calbindin cells represent a major interneuron subtype of the cortical/pallial regions, such as the basolateral amygdala, which are often analyzed in studies of tangential migration of interneurons from the subpallial ganglionic eminences to the pallium/cortex. However, previous evidence suggests that during development the calbindin cells may include more than one of the interneuron subtypes found in the adult pallium/cortex. Furthermore, in the adult basolateral amygdala, calbindin cells include a subpopulation of non-GABAergic (non-interneuron) cells. To better characterize these cells throughout development, in the present study we investigated the colocalization of calbindin, parvalbumin and GABA in cells of the mouse basolateral amygdala during late embryonic (E16.5) and several postnatal ages from birth until 4 weeks after birth (P0, P10 and P28). Our results indicate that CB, PV and GABA show a dynamic pattern of colocalization in cells of the mouse basolateral amygdalar nucleus throughout development. From E16.5 through P28, the majority of CB+ neurons and virtually all PV+ neurons are GABAergic. However, after P10, the percentage of GABAergic CB+ cells decline from 96% to 70%. Furthermore, while only 9% of CB+ neurons are PV+ at P10, this percentage raises to 42% at P28. At all postnatal ages studied, the majority of the PV+ cells are CB+, suggesting that PV+ interneurons develop postnatally mainly as a subpopulation within the CB+ cells of the basolateral amygdalar nucleus. These results are important for interpreting data from interneuron migration.

Calcium-binding proteins, neuronal nitric oxide synthase, and GABA help to distinguish different pallial areas in the developing and adult chicken. I. Hippocampal formation and hyperpallium.

To better understand the formation and adult organization of the avian pallium, we studied the expression patterns of gamma-aminobutyric acid (GABA), calbindin (CB), calretinin (CR), and neuronal nitric oxide synthase (nNOS) in the hippocampal formation and hyperpallium of developing and adult chicks. Each marker showed a specific spatiotemporal expression pattern and was expressed in a region (area)-specific but dynamic manner during development. The combinatorial expression of these markers was very useful for identifying and following the development of subdivisions of the chicken hippocampal formation and hyperpallium. In the hyperpallium, three separate radially arranged subdivisions were present since early development showing distinct expression patterns: the apical hyperpallium (CB-rich); the intercalated hyperpallium (nNOS-rich, CB-poor); the dorsal hyperpallium (nNOS-poor, CB-moderate). Furthermore, a novel division was identified (CB-rich, CR-rich), interposed between hyper- and mesopallium and related to the lamina separating both, termed laminar pallial nucleus. This gave rise at its surface to part of the lateral hyperpallium. Later in development, the interstitial nucleus of the apical hyperpallium became visible as a partition of the apical hyperpallium. In the hippocampal formation, at least five radial divisions were observed, and these were compared with the divisions proposed recently in adult pigeons. Of note, the corticoid dorsolateral area (sometimes referred as caudolateral part of the parahippocampal area) contained CB immunoreactivity patches coinciding with Nissl-stained cell aggregates, partially resembling the patches described in the mammalian entorhinal cortex. Each neurochemical marker was present in specific neuronal subpopulations and axonal networks, providing insights into the functional maturation of the chicken pallium.

Immunohistochemical localization of the vesicular glutamate transporter VGLUT2 in the developing and adult mouse claustrum.

We studied the immunoreactive expression pattern for the vesicular glutamate transporter VGLUT2 in the embryonic, postnatal and adult mouse dorsal claustrum, at the light and electron microscopic levels. VGLUT2 immunoreactivity in the dorsal claustrum starts to be observed at E16.5, with a dramatic increase towards P0. At this age, abundant VGLUT2-immunoreactive axons and puncta are observed in all pallial regions, including the claustral complex. From the first postnatal week, VGLUT2 immunoreactivity declines in several telencephalic areas, including the pallium, but abundant VGLUT2-immunoreactive fine axons and puncta remain in the claustrum. Beginning at E18.5, VGLUT2 immunoreactivity within the claustrum shows a characteristic arrangement: a central part of the region is practically devoid of VGLUT2 immunoreactivity, and it is surrounded by plenty of immunoreactive axon terminals forming a shell around it. This core/shell arrangement of the VGLUT2 immunoreactivity resembles the complementary expression of parvalbumin and calretinin described in the mouse claustrum [Real, M.A., Dávila, J.C., Guirado, S., 2003. Expression of calcium-binding proteins in the mouse claustrum. J. Chem. Neuroanat. 25, 151-160]. We observed immunoreactive neuronal cell bodies as well in the dorsal claustrum, but only at P0. Electron microscopic analysis reveals that VGLUT2 immunoreactivity in the developing and adult dorsal claustrum consists predominantly of presynaptic boutons making asymmetric synaptic contacts. These VGLUT2-immunoreactive boutons are observed as early as E16.5 and may be related to thalamo-claustral incoming fibers.

The ascending tectofugal visual system in amniotes: new insights.

Ascending tectal axons carrying visual information constitute a fiber pathway linking the mesencephalon with the dorsal thalamus and then with a number of telencephalic centers. The sauropsidian nucleus rotundus and its mammalian homologue(s) occupy a central position in this pathway. The aim of this study was analyzing the rotundic connections in reptiles and birds in relation with comparable connections in mammals, by using biotinylated dextran amines and the lipophilic carbocyanine dye DiI as tracing molecules. In general, rotundic connections in reptiles and birds are quite similar, especially with regards to pretectal and tectal afferences; as a novel finding, we describe varicose fibers arising from nucleus rotundus that reached the developing chick striatum. In addition, this study described the dorsal claustrum as a novel telencephalic target for the suprageniculate nucleus in mammals. Overall, telencephalic projections from the posterior/intralaminar complex of the mammalian thalamus can be compared with the telencephalic projections of the reptilian nucleus rotundus. With the exception of the isocortical connections, the mouse suprageniculate nucleus shares a number of afferent and efferent connections with the sauropsidian nucleus rotundus. Especially significant were the suprageniculate fibers reaching the striatum and then following to reach pallial derivatives such as the lateral amygdala (ventral pallium) and the dorsal claustrum (lateral pallium). These connections can be compared with the rotundic fibers reaching the ventromedial part of the anterior dorsal ventricular ridge in reptiles/entopallium in birds (ventral pallium) and the dorsolateral part of the anterior dorsal ventricular ridge in reptiles (lateral pallium), and probably the mesopallium in birds.

Semaphorin5A expression in the developing chick telencephalon.

In the present study, we analyzed the expression of Semaphorin5A (Sema5A), a gene implicated in axon guidance and many other processes of neuronal development, in the developing chick telencephalon. By using a heterologous mouse probe and in situ hybridization techniques, we showed distinct patterns of Sema5A expression within the chick telencephalon. In early development, Sema5A was present in pallial regions, mainly in the neuroepithelium and in the deep mantle of ventral and lateral pallia, and in the subpallium. As development proceeds, some ventral pallial derivatives maintained a moderate to strong Sema5A expression, whereas other lateral or dorsal pallial derivatives showed low to moderate expression of Sema5A. The overall expression of Sema5A during development in the chick telencephalon was similar to that reported in mouse. Moreover, the expression of Sema5A in mesencephalic, diencephalic, and telencephalic centers related to the tectofugal system suggests an important role of this gene in the development.

Distribution of GABA, calbindin and nitric oxide synthase in the developing chick entopallium.

The distribution of GABA, calbindin and neuronal nitric oxide synthase (nNOS) was analyzed in the developing avian entopallium. The study was carried out in chick embryos from embryonic day (E)8 to hatching postnatal day (P)0, using immunohistochemical methods. At E8, GABA-positive cells were observed in pallial regions. Neither calbindin nor nNOS-immunoreactive cells were observed. At E10, the number of GABA neurons in the prospective entopallium increased and also nNOS cells were observed. Lightly stained nNOS neurons predominated over intensely stained ones. Calbindin immunoreactivity was not observed in the entopallium. At E12, the entopallial complex appeared as the pallial region displaying the highest density of GABA neurons. Also the whole entopallium displayed an intensely stained calbindin neuropil with many embedded stained cells. From E12 on, there was a decrease in the expression of nNOS. At E14-16, both GABA and calbindin-immunoreactive neurons were numerous and homogeneously distributed within the entopallium. The whole entopallium displayed a moderately stained neuropil. From E18 to P0, GABA and nNOS immunoreactivities remained similar to previous stages. At these stages, calbindin immunoreactivity within the entopallium consisted of a moderately stained central region bordered dorsally by a pale stained region. These two areas could correspond to the entopallial core and the perientopallial belt, respectively.

Distribution of nitric oxide-producing neurons in the developing and adult mouse amygdalar basolateral complex.

We analysed the expression of neuronal nitric oxide synthase (nNOS) in the mouse amygdalar basolateral complex (BLC) from embryonic day 15.5 to adult, using standard immunohistochemical methods. Our results indicate that each nucleus of the amygdalar basolateral complex displays a distinct nNOS expression pattern, which is established during the ontogenesis with minor changes in the adult. The basomedial nucleus (BM) exhibited the highest nNOS immunoreactivity in the basolateral complex, observable from early embryonic stages, whereas the lateral nucleus displayed the lowest level of immunoreactivity. The expression pattern for nNOS in the basolateral nucleus differed substantially from that of the lateral and basomedial nuclei, showing a slightly increase in the number of nNOS cells and neuropil staining from intermediate developmental until early postnatal stages. Two distinct types of nitrergic neurons, densely and lightly stained neurons, were observed in the developing basolateral complex. Both types of putative nitrergic neurons were unevenly distributed in the basolateral complex. On the basis of previous data regarding the colocalization between nNOS and GABA in the mouse claustrum, we suggest that nNOS expressing neurons in the basolateral amygdalar complex are both GABAergic and non-GABAergic.

Development of neurons and fibers containing calcium binding proteins in the pallial amygdala of mouse, with special emphasis on those of the basolateral amygdalar complex.

We studied the development of neurons and fibers containing calbindin, calretinin, and parvalbumin in the mouse pallial amygdala, with special emphasis on those of the basolateral amygdalar complex. Numerous calbindin-immunoreactive (CB+) cells were observed in the incipient basolateral amygdalar complex and cortical amygdalar area from E13.5. At E16.5, CB+ cells became more abundant in the lateral and basolateral nuclei than in the basomedial nucleus, showing a pattern very similar to that of gamma-aminobutyric acid (GABA)ergic neurons. Many CB+ cells observed in the pallial amygdala appeared to originate in the anterior entopeduncular area/ganglionic eminences of the subpallium. The density of CB+ cells gradually increased in the pallial amygdala until the first postnatal week and appeared to decrease later, coinciding with the postnatal appearance of parvalbumin cells and raising the possibility of a partial phenotypic shift. Calretinin (CR) immunoreactivity could be observed in a few cells and fibers in the pallial amygdala at E14.5, and by E16.5 it became a good marker of the different nuclei of the basolateral amygdalar complex. Numerous CB+ and CR+ varicosities, part of which have an intrinsic origin, were observed in the basolateral amygdalar complex from E16.5, and some surrounded unstained perikarya and/or processes before birth, indicating an early formation of inhibitory networks. Each calcium binding protein showed a distinct spatiotemporal expression pattern of development in the mouse pallial amygdala. Any alteration in the development of neurons and fibers containing calcium binding proteins of the pallial amygdala may result in important disorders of emotional and social behavior.

Embryonic and postnatal development of GABA, calbindin, calretinin, and parvalbumin in the mouse claustral complex.

We analyzed the development of immunoreactive expression patterns for the neurotransmitter gamma-aminobutyric acid (GABA) and the calcium-binding proteins calbindin, calretinin, and parvalbumin in the embryonic and postnatal mouse claustral complex. Each calcium-binding protein shows a different temporal and spatial pattern of development. Calbindin-positive cells start to be seen very early during embryogenesis and increase dramatically until birth, thus becoming the most abundant cell type during embryonic development, especially in the ventral pallial part of the claustrum. The distribution of calbindin neurons throughout the claustrum during embryonic development partly parallels that of GABA neurons, suggesting that at least part of the calbindin neurons of the claustral complex are GABAergic and originate in the subpallium. Parvalbumin cells, on the other hand, start to be seen only postnatally, and their number then increases while the density of calbindin neurons decreases. Based on calretinin expression in axons, the core/shell compartments of the dorsal claustrum start to be clearly seen at embryonic day 18.5 and may be related to the development of the thalamoclaustral input. Comparison with the expression of Cadherin 8, a marker of the developing dorsolateral claustrum, indicates that the core includes a central part of the dorsolateral claustrum, whereas the shell includes a peripheral area of the dorsolateral claustrum, plus the adjacent ventromedial claustrum. The present data on the spatiotemporal developmental patterns of several subtypes of GABAergic neurons in the claustral complex may help for future studies on temporal lobe epilepsies, which have been related to an alteration of the GABAergic activity.