Search results for "Ventral"
showing 10 items of 180 documents
The "olfactostriatum" of snakes: a basal ganglia vomeronasal structure in tetrapods.
2005
The olfactostriatum is a portion of the basal ganglia of snakes situated ventromedially to the nucleus accumbens proper. It receives a major vomeronasal input from the nucleus sphericus, the primary target of accessory olfactory bulb efferents. Recently, the ophidian olfactostriatum has been characterized on the basis of chemoarchitecture (distribution of serotonin, neuropeptide Y and tyrosine hydroxylase) and hodology (afferent and efferent connections). In contrast to the nucleus accumbens proper, the olfactostriatum is densely immunoreactive for serotonin and neuropeptide Y and sparsely immunoreactive for tyrosine hydroxylase. The nucleus accumbens proper and the olfactostriatum share mo…
Amygdala
2015
The amygdala is considered a key center in managing emotional information and its dysfunction is at the base of disorders ranging through anxiety, depression, PTSD and autism. However, the amygdala seems heterogeneous both structurally (with pallial and supallial components) and functionally. Thus, whereas cortical and thalamic multimodal sensory inputs enter the basolateral complex, the corticomedial amygdala is dominated by olfactory and vomeronasal inputs. Intrinsic amygdaloid circuitry, connects these two amygdaloid divisions and convey processed information to the main amygdala outputs. The pallial amygdala is the main source for telencephalic outputs to associative cortical areas (e.g…
The pattern of neuroblast formation, mitotic domains and proneural gene expression during early brain development in Drosophila.
2003
In the Drosophila embryo, studies on CNS development have so far mainly focused on the relatively simply structured ventral nerve cord. In the trunk, proneural genes become expressed in small cell clusters at specific positions of the ventral neuroectoderm. A lateral inhibition process mediated by the neurogenic genes ensures that only one cell within each proneural cluster delaminates as a neural stem cell (neuroblast). Thus, a fixed number of neuroblasts is formed, according to a stereotypical spatiotemporal and segmentally repeated pattern, each subsequently generating a specific cell lineage. Owing to higher complexity and hidden segmental organisation, the mechanisms underlying the dev…
Inhibitory effect of A10 dopaminergic neurons of the ventral tegmental area on the orienting response evoked by acoustic stimulation in the cat.
1998
Abstract The effect of bilateral electric stimulation of A10 dopaminergic neurons of the ventral tegmental area (80–300 μA, 20–50 Hz, 0.1–0.5 ms, 2 s duration) on latency and duration of the orienting response, evoked by acoustic stimuli (4500–8000 Hz, 2 s), was studied in the cat. A10 neuron stimulation, simultaneous with the acoustic one, was performed with threshold parameters inducing minimal behavioral signs (head searching movement, sniffing, increase in alertness). By means of a videoanalysis system, a statistically significant increase, both of latency and duration of the response, was observed. The possible role of dopamine was studied administrating sulpiride (20 mg/kg IP), a dopa…
Evolution of vertebrate survival circuits
2018
Evolution selects those adaptive features that increase reproductive probabilities and facilitate survival. Analysing the brain circuits mediating risk-avoidance (e.g. defense) and those allowing reward-seeking (motivated) behaviours in different vertebrates leads to several main conclusions. First, circuits mediating risk-avoidance are similar in all studied vertebrates, where they include amygdala homologues located in the posterior half of the cerebral hemispheres, in close relationship with the chemosensory systems. Second, in all vertebrates, reward-seeking behaviours involve the activity of tegmento-striatal dopaminergic pathways, plus other inputs to the ventral striatum, including a…
Histological characteristics of the vertebral intercentra of Metoposaurus diagnosticus (Temnospondyli) from the Upper Triassic of Krasiejów (Upper Si…
2012
ABSTRACTOsteohistological characteristics of the large temnospondyl amphibian Metoposaurus diagnosticus from the Upper Triassic of Poland (Krasiejów locality) were determined using vertebral intercentra thin-sections from different regions and growth stages. The intercentra showed a trabecular structure in both the endochondral and periosteal domains. Endochondral ossification developed first, and the primary bone occurs near the periphery with a higher degree of remodelling in the centre. Periosteal bone deposition begins later; first on the ventral side, continuing laterally and finally onto the dorsal side. Periosteal growth rate was initially very rapid, and then subsequently decreased …
Amygdalostriatal projections in reptiles: A tract-tracing study in the lizardPodarcis hispanica
2004
Whereas the lacertilian anterior dorsal ventricular ridge contains unimodal sensory areas, its posterior part (PDVR) is an associative center that projects to the hypothalamus, thus being comparable to the amygdaloid formation. To further understand the organization of the reptilian cerebral hemispheres, we have used anterograde and retrograde tracing techniques to study the projections from the PDVR and adjoining areas (dorsolateral amygdala, DLA; deep lateral cortex, dLC; nucleus sphericus, NS) to the striatum in the lizard Podarcis hispanica. This information is complemented with a detailed description of the organization of the basal telencephalon of Podarcis. The caudal aspect of the d…
Serotonin–dopamine interaction: an overview
2008
Central serotonergic and dopaminergic systems play a critical role in the regulation of normal and abnormal behaviours. Moreover, recent evidence suggests that the dysfunction of dopamine (DA) and serotonin (5-hydroxytriptamine, 5-HT) neurotransmission might underlie the pathophysiology of neuropsychiatric disorders, including depression, schizophrenia, attention deficit hyperactivity disorders, drug abuse, Gilles de la Tourette's syndrome and Parkinson's disease.
Dysfunction of the mesolimbic circuit to food odors in women with anorexia and bulimia nervosa: A fMRI study
2019
Brain reward dysfunction in eating disorders has been widely reported. However, whether the neural correlates of hedonic and motivational experiences related to food cues are differentially affected in anorexia nervosa of restrictive type (ANr), bulimia nervosa (BN), and healthy control (HC) participants remains unknown. Here, 39 women (14 ANr, 13 BN, and 12 HC) underwent fMRI while smelling food or non-food odors in hunger and satiety states during liking and wanting tasks. ANr and BN patients reported less desire to eat odor-cued food and odor-cued high energy-density food (EDF), respectively. ANr patients exhibited lower ventral tegmental area (VTA) activation than BN patients to food od…
Topography of somatostatin gene expression relative to molecular progenitor domains during ontogeny of the mouse hypothalamus
2010
The hypothalamus comprises alar, basal, and floor plate developmental compartments. Recent molecular data support a rostrocaudal subdivision into rostral (terminal) and caudal (peduncular) halves. In this context, the distribution of neuronal populations expressing somatostatin (Sst) mRNA was analyzed in the developing mouse hypothalamus, comparing with the expression pattern of the genes Orthopedia (Otp), Distal-less 5 (Dlx5), Sonic Hedgehog (Shh), and Nk2 homeobox 1 (Nkx2.1). At embryonic day 10.5 (E10.5), Sst mRNA was first detectable in the anterobasal nucleus, a Nkx2.1-, Shh-, and Otp-positive basal domain. By E13.5, nascent Sst expression was also related to two additional Otp-positiv…