Search results for "Nucleus"
showing 10 items of 1803 documents
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…
Kappa opioid receptor blockade in the nucleus accumbens shell prevents sex-dependent alcohol deprivation effect induced by inflammatory pain.
2021
ABSTRACT Pain-induced negative affect reduces life quality of patients by increasing psychiatric comorbidities, including alcohol use disorders (AUDs). Indeed, clinical data suggest pain as a risk factor to suffer AUDs, predicting relapse drinking in abstinent patients. Here, we analyse the impact of pain on alcohol relapse and the role of kappa opioid receptor (KOR) activation in mediating these pain-induced effects because KORs play an important role in pain-driven negative affect and AUD. Female and male Sprague-Dawley rats underwent 2 alcohol intermittent access periods separated by a forced abstinence period. The complete Freund adjuvant model of inflammatory pain was introduced during…
Therapeutic-like properties of a dopamine uptake inhibitor in animal models of amphetamine addiction.
2010
N-substituted benztropine (BZT) analogs are molecules that display high affinity for the dopamine transporter (DAT), therapeutic-like effects in animal models of cocaine abuse, and psychopharmacological characteristics consistent with those of a substitute medication for cocaine addiction. Since amphetamine (Amph) and cocaine share mechanisms of action at the DAT, we evaluated the effectiveness of a BZT analog in animal models of Amph addiction. We tested in mice and rats the effects of the BZT derivative, 3α-[bis(4-fluorophenyl)methoxy]-tropane (AHN-1055), on Amph-induced conditioned place preference (CPP), locomotor activity, sensitization, self-administration and ΔFosB accumulation in th…
Investigations on day-night differences of vesicle densities in synapses of the rat suprachiasmatic nucleus
1990
The present study was conducted to test whether the well-known circadian alterations in physiological and metabolical parameters of the hypothalamic suprachiasmatic nucleus (SCN) are accompanied by day-night differences in the number of vesicles in intrinsic synapses of the nucleus. Two groups of 5 adult male rats each were killed at mid-light or mid-dark, respectively, by perfusion with Karnovsky's fluid. The SCN were removed and processed for routine electron microscopy. In medial parts of the nucleus, synapses were characterized as being of Gray type I (asymmetrical), Gray type II (symmetrical) or of intermediate form, and the vesicles per synaptic profile (VPSP) were counted over a defi…
Components and connections of the circadian timing system in mammals
1996
The circadian timing system is a neural network consisting of the hypothalamic suprachiasmatic nucleus, aided by the retina, other hypothalamic nuclei, autonomic regions of the spinal cord, sympathetic ganglia and the pineal gland. Extensive studies conducted over the last two decades have unravelled the principal items of its functional neuroanatomy. The system is responsible for the generation of the circadian rhythm, its synchronization by environmental factors such as light, and its mediation with respect to morphological, physiological and biochemical parameters of mammals that exhibit distinct alterations throughout the 24-h cycle. This review characterizes the brain sites involved an…
Dynamic Tuning of Viscoelastic Hydrogels with Carbonyl Iron Microparticles Reveals the Rapid Response of Cells to Three-Dimensional Substrate Mechani…
2021
Current methods to dynamically tune three-dimensional hydrogel mechanics require specific chemistries and substrates that make modest, slow, and often irreversible changes to their mechanical properties, exclude the use of protein-based scaffolds, or alter hydrogel microstructure and pore size. Here, we rapidly and reversibly alter the mechanical properties of hydrogels consisting of extracellular matrix proteins and proteoglycans by adding carbonyl iron microparticles (MP) and applying external magnetic fields. This approach drastically alters hydrogel mechanics: rheology reveals that application of a 4,000 Oe magnetic field to a 5 mg/mL collagen hydrogel containing 10 wt% MPs increases th…
Nucleus-driven crystallization of amorphous Ge2Sb2Te5: A density functional study
2012
Early stages of nucleus-driven crystallization of the prototype phase change material Ge${}_{2}$Sb${}_{2}$Te${}_{5}$ have been studied by density functional/molecular dynamics simulations for amorphous samples (460 and 648 atoms) at 500, 600, and 700 K. All systems assumed a fixed cubic seed of 58 atoms and 6 vacancies. Crystallization occurs within 600 ps for the 460-atom system at 600 and 700 K, and signs of crystallization (nucleus growth, percolation) are present in the others. Crystallization is accompanied by an increase in the number of ``$ABAB$ squares'' ($A$: Ge, Sb, $B$: Te), and atoms of all elements move significantly. There is no evidence of cavity movement to the crystal-glass…
Interfacial premelting of ice in nano composite materials
2018
Physical chemistry, chemical physics 21, 3734 - 3741 (2019). doi:10.1039/C8CP05604H
Investigation of E0 Transition in 74Kr
2000
The N = Z+2 nucleus 74Kr has been investigated by in-beam conversion electron (CE) and γ ray spectroscopy. The electric-monopole (E0) decay was examined in order to confirm the evidence for a low-lying isomeric 0+2 state and to give insight into the mixing between the predicted coexisting prolate and oblate shapes.
Cytochalasin B selectively releases ovalbumin mRNA precursors but not the mature ovalbumin mRNA from hen oviduct nuclear matrix
1987
Hen oviduct nuclear matrix-bound mature ovalbumin mRNA is released from the matrix in the presence of ATP, while the ovalbumin mRNA precursors remain bound to this structure. Detachment of the mature mRNA from the matrix by ATP as well as ATP-dependent efflux of mRNA from isolated nuclei were found to be inhibited by cytochalasin B. On the other hand, in the absence of ATP, cytochalasin B exclusively caused the release (and nucleocytoplasmic efflux) of the ovalbumin messenger precursors, but not of the mature mRNA. After cytochalasin B treatment, actin could be detected in the matrix supernatant. Phalloidin which stabilizes actin filaments did not cause RNA liberation in the absence of ATP,…