Search results for "Ventral"
showing 10 items of 180 documents
Hippocampal dopamine receptors modulate cFos expression in the rat nucleus accumbens evoked by chemical stimulation of the ventral hippocampus
2005
Recently, we have shown that D1 and D2 receptors in the ventral hippocampus (VH) modulate both the locomotor activation and the increase in dopamine (DA) levels in the rat nucleus accumbens (NAc) induced by NMDA stimulation of the VH. In the present study we analyze the possible role of VH D1 and D2 receptors in the modulation of the cFos expression in NAc (core and shell subregions) and in dorsal striatum. This was assessed by immunohistochemical analysis of cFos expression in the rat brains after retro-dialysis application of NMDA (50mM, 10 min) into VH, in absence and in presence of either the D1/D5 receptor antagonist SCH 23390 (100 and 250 microM, 60 min) or the D2 receptor antagonist …
Insulin acts at different CNS sites to decrease acute sucrose intake and sucrose self-administration in rats.
2008
Findings from our laboratory and others have demonstrated that the hormone insulin has chronic effects within the CNS to regulate energy homeostasis and to decrease brain reward function. In this study, we compared the acute action of insulin to decrease intake of a palatable food in two different behavioral tasks—progressive ratios sucrose self-administration and mu opioid-stimulated sucrose feeding—when administered into several insulin-receptive sites of the CNS. We tested insulin efficacy within the medial hypothalamic arcuate (ARC) and paraventricular (PVN) nuclei, the nucleus accumbens, and the ventral tegmental area. Administration of insulin at a dose that has no chronic effect on …
Episodic Social Stress-Escalated Cocaine Self-Administration: Role of Phasic and Tonic Corticotropin Releasing Factor in the Anterior and Posterior V…
2016
Intermittent social defeat stress escalates later cocaine self-administration. Reward and stress both activate ventral tegmental area (VTA) dopamine neurons, increasing downstream extracellular dopamine concentration in the medial prefrontal cortex and nucleus accumbens. The stress neuropeptide corticotropin releasing factor (CRF) and its receptors (CRF-R1, CRF-R2) are located in the VTA and influence dopaminergic activity. These experiments explore how CRF release and the activation of its receptors within the VTA both during and after stress influence later cocaine self-administration in rats.In vivomicrodialysis of CRF in the VTA demonstrated that CRF is phasically released in the poster…
On the Establishment of Polarity in Polychaete Eggs
1990
The study of Spiralian development began about a hundred years ago when Whitman (1878) published a description of the development of the leech, Clepsine marginata. Subsequently, Spiralian development became popular because the developmental fate of each individual blastomere can be determined precisely from the cell lineage. About the turn of the century several extensive papers describing the cell lineages of various molluscs (e.g. Blochmann, 1881, 1883; Kofoid, 1895; Conklin, 1897; Wierzejski 1905) and annelids (e.g. Wilson, 1892; Mead, 1897; Woltereck, 1904) appeared. From these studies it became clear that the general principles of mollusc and annelid development (and to a much lesser d…
Effect Of Inflammatory Pain On Alcohol-Induced Dopamine Release In The Nucleus Accumbens: Behavioural Implications In Rat Models
2019
AbstractRecent studies have drawn the attention to the link between Alcohol Use Disorder (AUD) and the presence of pain. Indeed, the correct management of pain in patients with a previous history of AUD has been reported to decrease the risk of relapse in alcohol drinking, suggesting that in this prone population, pain may increase the vulnerability to relapse. Previous data in male rats revealed that inflammatory pain desensitizes mu opioid receptors (MORs) in the ventral tegmental area (VTA) and increases intake of high doses of heroine. Due to the relevant role of MORs in alcohol effects, we hypothesize that pain may also alter alcohol reinforcing properties and therefore affect alcohol …
A Critical Period for Prefrontal Network Configurations Underlying Psychiatric Disorders and Addiction
2020
The medial prefrontal cortex (mPFC) has been classically defined as the brain region responsible for higher cognitive functions, including the decision-making process. Ample information has been gathered during the last 40 years in an attempt to understand how it works. We now know extensively about the connectivity of this region and its relationship with neuromodulatory ascending projection areas, such as the dorsal raphe nucleus (DRN) or the ventral tegmental area (VTA). Both areas are well-known regulators of the reward-based decision-making process and hence likely to be involved in processes like evidence integration, impulsivity or addiction biology, but also in helping us to predict…
Distribution, classification, and development ofDrosophila glial cells in the late embryonic and early larval ventral nerve cord.
1994
To facilitate the investigation of glial development inDrosophila, we present a detailed description of theDrosophila glial cells in the ventral nerve cord. A GAL4 enhancer-trap screen for glial-specific expression was performed. Using UAS-lacZ and UAS-kinesin-lacZ as reporter constructs, we describe the distribution and morphology of the identified glial cells in the fully differentiated ventral nerve cord of first-instar larvae just after hatching. The three-dimensional structure of the glial network was reconstructed using a computer. Using the strains with consistent GAL4 expression during late embryogenesis, we traced back the development of the identified cells to provide a glial map …
Dorsoventral Patterning of the Brain: A Comparative Approach
2009
Development of the central nervous system (CNS) involves the transformation of a two-dimensional epithelial sheet of uniform ectodermal cells, the neuroectoderm, into a highly complex three-dimensional structure consisting of a huge variety of different neural cell types. Characteristic numbers of each cell type become arranged in reproducible spatial patterns, which is a prerequisite for the establishment of specific functional contacts. Specification of cell fate and regional patterning critical depends on positional information conferred to neural stem cells early in the neuroectoderm. This chapter compares recent findings on mechanisms that control the specification of cell fates along …
Antagonistic roles for Ultrabithorax and Antennapedia in regulating segment-specific apoptosis of differentiated motoneurons in the Drosophila embryo…
2008
The generation of morphological diversity among segmental units of the nervous system is crucial for correct matching of neurons with their targets and for formation of functional neuromuscular networks. However, the mechanisms leading to segment diversity remain largely unknown. We report here that the Hox genes Ultrabithorax (Ubx) and Antennapedia (Antp) regulate segment-specific survival of differentiated motoneurons in the ventral nerve cord of Drosophilaembryos. We show that Ubx is required to activate segment-specific apoptosis in these cells, and that their survival depends on Antp. Expression of the Ubx protein is strongly upregulated in the motoneurons shortly before they undergo a…
Ems and Nkx6 are central regulators in dorsoventral patterning of the Drosophila brain
2009
In central nervous system development, the identity of neural stem cells (neuroblasts) critically depends on the precise spatial patterning of the neuroectoderm in the dorsoventral (DV) axis. Here, we uncover a novel gene regulatory network underlying DV patterning in the Drosophila brain, and show that the cephalic gap gene empty spiracles (ems) and the Nk6 homeobox gene (Nkx6) encode key regulators. The regulatory network implicates novel interactions between these and the evolutionarily conserved homeobox genes ventral nervous system defective (vnd), intermediate neuroblasts defective (ind) and muscle segment homeobox (msh). We show that Msh cross-repressively interacts with Nkx6 to sust…