keyword
MENU ▼
Read by QxMD icon Read
search

Dopamine antagonists

keyword
https://www.readbyqxmd.com/read/28218041/guibourtia-tessmannii-induced-fictive-ejaculation-in-spinal-male-rat-involvement-of-d1-d2-like-receptors
#1
Patrick Brice Deeh Defo, Elvis Asongu, Modeste Nya Wankeu, Esther Ngadjui, Georges Romeo Bonsou Fazin, François Xavier Kemka, Miguel Carro-Juarez, Albert Kamanyi, Pierre Kamtchouing, Pierre Watcho
CONTEXT: Guibourtia tessmannii (Caesalpiniaceae) is a plant traditionally used as aphrodisiac. We previously reported the pro-ejaculatory effects of the aqueous and methanol extracts of G. tesmannii in spinal male rat. However, the mechanism underlying such effects has not been elucidated. OBJECTIVE: This study characterizes the dopaminergic sub-type receptors involved in G. tesmannii-induced ejaculation in male Wistar rat. MATERIALS AND METHODS: Urethane-anesthetized spinal male rats were intravenously treated with saline solution (1 mL/kg, control); dopamine (0...
December 2017: Pharmaceutical Biology
https://www.readbyqxmd.com/read/28213070/selective-a2a-receptors-blockade-reduces-degeneration-of-substantia-nigra-dopamine-neurons-in-a-rotenone-induced-rat-model-of-parkinson-s-disease-a-histological-study
#2
Ahmed M Fathalla, Amira M Soliman, Ahmed A Moustafa
Parkinson's disease (PD) is characterized by a loss of dopaminergic neurons in the substantia nigra pars compacta (SNpc). Adenosine is a neuromodulator that inhibit the release of dopamine via a disinhibitory mechanism. In this study, we investigated the neuroprotective effect of 8-cyclopentyl-1,3-dipropylxanthine and ZM241385 (respectively, A1 and A2A receptors antagonists), on nigrostriatal dopamine neurons degradation reduction in a rotenone-induced PD model using histopathological and immunohistochemical methods...
February 15, 2017: Neuroscience Letters
https://www.readbyqxmd.com/read/28213064/juvenile-treatment-with-a-novel-mglur2-agonist-mglur3-antagonist-compound-ly395756-reverses-learning-deficits-and-cognitive-flexibility-impairments-in-adults-in-a-neurodevelopmental-model-of-schizophrenia
#3
Meng-Lin Li, Yelena Gulchina, Sarah A Monaco, Bo Xing, Brielle R Ferguson, Yan-Chun Li, Feng Li, Xi-Quan Hu, Wen-Jun Gao
Schizophrenia (SCZ) is a neurodevelopmental psychiatric disorder, in which cognitive function becomes disrupted at early stages of the disease. Although the mechanisms underlying cognitive impairments remain unclear, N-methyl-D-aspartate receptors (NMDAR) hypofunctioning in the prefrontal cortex (PFC) has been implicated. Moreover, cognitive symptoms in SCZ are usually unresponsive to treatment with current antipsychotics and by onset, disruption of the dopamine system, not NMDAR hypofunctioning, dominates the symptoms...
February 14, 2017: Neurobiology of Learning and Memory
https://www.readbyqxmd.com/read/28212943/effects-of-acute-dopaminergic-and-serotonergic-manipulations-in-the-aci-paradigm-depend-on-the-basal-valence-of-cognitive-judgement-bias-in-rats
#4
Joanna Golebiowska, Rafal Rygula
Recent findings have revealed that pharmacological enhancement of dopaminergic (DA) function by the administration of a DA precursor (dihydroxy-L-phenylalanine; L-DOPA), but not the selective serotonin reuptake inhibitor (SSRI) citalopram, increases an optimism bias in humans. To test whether dopamine might play a similar role in non-human animals, in the present study, we evaluated the effects of acute injections of L-DOPA, the D2 receptor antagonist haloperidol, and the SSRI escitalopram on cognitive judgement bias of rats in the ambiguous-cue interpretation (ACI) paradigm...
February 14, 2017: Behavioural Brain Research
https://www.readbyqxmd.com/read/28212942/activation-of-type-4-dopaminergic-receptors-in-the-prelimbic-area-of-medial-prefrontal-cortex-is-necessary-for-the-expression-of-innate-fear-behavior
#5
Macarena D Vergara, Victor N Keller, José A Fuentealba, Katia Gysling
The prelimbic area (PL) of the medial Prefrontal cortex (mPFC) is involved in the acquisition and expression of conditioned and innate fear. Both types of fear share several neuronal pathways. It has been documented that dopamine (DA) plays an important role in the regulation of aversive memories in the mPFC. The exposure to an aversive stimulus, such as the smell of a predator odor or the exposure to footshock stress is accompanied by an increase in mPFC DA release. Evidence suggests that the type 4 dopaminergic receptor (D4R) is the molecular target through which DA modulates fear expression...
February 14, 2017: Behavioural Brain Research
https://www.readbyqxmd.com/read/28202786/dopamine-modulates-adaptive-prediction-error-coding-in-the-human-midbrain-and-striatum
#6
Kelly M J Diederen, Hisham Ziauddeen, Martin D Vestergaard, Tom Spencer, Wolfram Schultz, Paul C Fletcher
Learning to optimally predict rewards requires agents to account for fluctuations in reward value. Recent work suggests that individuals can efficiently learn about variable rewards through adaptation of the learning rate, and coding of prediction errors relative to reward variability. Such adaptive coding has been linked to midbrain dopamine neurons in nonhuman primates, and evidence in support for a similar role of the dopaminergic system in humans is emerging from fMRI data. Here, we sought to investigate the effect of dopaminergic perturbations on adaptive prediction error coding in humans, using a between-subject, placebo-controlled pharmacological fMRI study with a dopaminergic agonist (bromocriptine) and antagonist (sulpiride)...
February 15, 2017: Journal of Neuroscience: the Official Journal of the Society for Neuroscience
https://www.readbyqxmd.com/read/28201961/development-and-characterization-pulsatile-microspheres-of-nifedipine-for-hypertension
#7
Rahul Taneja, Ghanshyam Das Gupta
AIM AND BACKGROUND: To develop pulsatile microspheres of Nifedipine blend of polymers Carbopol 971P and Eudragit RS100 for antihypertensive to release the drug at a particular lag time. METHODS: Pulsatile nifedipine microspheres were prepared using blend of Carbopol 971P and Eudragit RS100 at different ratio in a mixture of solvents. Formulations were prepared and optimized on the basis of particle size, percentage yield and drug entrapment efficiency. Optimized formulations were further analyzed at different resolutions per minute (rpm) by optical microscopy, scanning electron microscopy (SEM), in-vitro dissolution studies and kinetics model...
February 12, 2017: Recent Patents on Drug Delivery & Formulation
https://www.readbyqxmd.com/read/28198465/fatigue-related-impairments-in-oculomotor-control-are-prevented-by-norepinephrine-dopamine-reuptake-inhibition
#8
Charlotte J W Connell, Benjamin Thompson, Jason Turuwhenua, Alexa Srzich, Nicholas Gant
Fatigue-induced reductions in saccade velocity have been reported following acute, prolonged exercise. Interestingly, the detrimental impact of fatigue on oculomotor control can be prevented by a moderate dose of caffeine. This effect may be related to central catecholamine upregulation via caffeine's action as an adenosine antagonist. To test this hypothesis, we compared the protective effect of caffeine on oculomotor control post-exercise to that of a norepinephrine-dopamine reuptake inhibitor. Within a placebo-controlled crossover design, 12 cyclists consumed placebo, caffeine or a norepinephrine-dopamine reuptake inhibitor (bupropion) during 180 minutes of stationary cycling...
February 15, 2017: Scientific Reports
https://www.readbyqxmd.com/read/28192174/does-genetic-bdnf-deficiency-in-rats-interact-with-neurotransmitter-control-of-prepulse-inhibition-implications-for-schizophrenia
#9
Maarten van den Buuse, Davina Biel, Kathrin Radscheit
Several studies have suggested a role of BDNF in the development of schizophrenia. For example, post-mortem studies have shown significantly reduced levels of BDNF protein expression in the brain of schizophrenia patients. We investigated the relationship between reduced levels of BDNF in the brain and the regulation of prepulse inhibition (PPI), a behavioral endophenotype of schizophrenia. We used BDNF heterozygous mutant rats which display a 50% decrease of mature BDNF protein levels. Previously, we observed normal baseline PPI and responses to the dopamine D1/D2 receptor agonist, apomorphine, in these rats...
February 10, 2017: Progress in Neuro-psychopharmacology & Biological Psychiatry
https://www.readbyqxmd.com/read/28188762/effects-of-the-5-ht6-receptor-antagonist-idalopirdine-on-extracellular-levels-of-monoamines-glutamate-and-acetylcholine-in-the-rat-medial-prefrontal-cortex
#10
Arne Mørk, Rasmus Vinther Russell, Inge E M de Jong, Gennady Smagin
Idalopirdine (Lu AE58054) is a high affinity and selective antagonist for the human serotonin 5-HT6 receptor (Ki 0.83nM) in phase III development for mild-to-moderate Alzheimer's disease as an adjunct therapy to acetylcholinesterase inhibitors (AChEIs). We have studied the effects of idalopirdine on extracellular levels of monoamines, glutamate and acetylcholine in the medial prefrontal cortex (mPFC) of freely-moving rats using microdialysis. Idalopirdine (10mg/kg p.o.) increased extracellular levels of dopamine, noradrenaline and glutamate in the mPFC and showed a trend to increase serotonin levels...
February 7, 2017: European Journal of Pharmacology
https://www.readbyqxmd.com/read/28188355/repeated-mdma-administration-increases-mdma-produced-locomotor-activity-and-facilitates-the-acquisition-of-mdma-self-administration-role-of-dopamine-d2-receptor-mechanisms
#11
Ross van de Wetering, Susan Schenk
RATIONALE: Repeated exposure to ±3, 4-methylenedioxymethamphetamine (MDMA) produces sensitization to MDMA-produced hyperactivity, but the mechanisms underlying the development of this sensitized response or the relationship to the reinforcing effects of MDMA is unknown. OBJECTIVES: This study determined the effect of a sensitizing regimen of MDMA exposure on the acquisition of MDMA self-administration and investigated the role of dopamine D2 receptor mechanisms...
February 10, 2017: Psychopharmacology
https://www.readbyqxmd.com/read/28187160/the-effects-of-dopamine-receptor-1-and-2-agonists-and-antagonists-on-sexual-and-aggressive-behaviors-in-male-green-anoles
#12
Alexandra N Smith, David Kabelik
The propensity to exhibit social behaviors during interactions with same-sex and opposite-sex conspecifics is modulated by various neurotransmitters, including dopamine. Dopamine is a conserved neurotransmitter among vertebrates and dopaminergic receptors are also highly conserved among taxa. Activation of D1 and D2 dopamine receptor subtypes has been shown to modulate social behaviors, especially in mammalian and avian studies. However, the specific behavioral functions of these receptors vary across taxa...
2017: PloS One
https://www.readbyqxmd.com/read/28186762/synthesis-and-pharmacological-characterization-of-novel-trans-cyclopropylmethyl-linked-bivalent-ligands-that-exhibit-selectivity-and-allosteric-pharmacology-at-the-dopamine-d3-receptor-d3r
#13
Vivek Kumar, Amy E Moritz, Thomas M Keck, Alessandro Bonifazi, Michael P Ellenberger, Christopher D Sibley, R Benjamin Free, Lei Shi, J Robert Lane, David R Sibley, Amy Hauck Newman
The development of bitopic ligands directed toward D2-like receptors has proven to be of particular interest to improve the selectivity and/or affinity of these ligands and as an approach to modulate and bias their efficacies. The structural similarities between dopamine D3 receptor (D3R)-selective molecules that display bitopic or allosteric pharmacology and those that are simply competitive antagonists are subtle and intriguing. Herein we synthesized a series of molecules in which the primary and secondary pharmacophores were derived from the D3R-selective antagonists SB269,652 (1) and SB277011A (2) whose structural similarity and pharmacological disparity provided the perfect templates for SAR investigation...
February 10, 2017: Journal of Medicinal Chemistry
https://www.readbyqxmd.com/read/28186690/reduced-levels-of-cacna1c-attenuate-mesolimbic-dopamine-system-function
#14
Chantelle E Terrillion, David T Dao, Roger Cachope, Mary Kay Lobo, Adam C Puche, Joseph F Cheer, Todd D Gould
Genetic variation in CACNA1C, which codes for the L-type calcium channel (LTCC) Cav 1.2, is associated with clinical diagnoses of bipolar disorder, depression, and schizophrenia. Dysregulation of the mesolimbic dopamine (DA) system is linked to these syndromes and LTCCs are required for normal DAergic neurotransmission between the ventral tegmental area (VTA) and nucleus accumbens (NAc). It is unclear, however, how variations in CACNA1C genotype, and potential subsequent changes in expression levels in these regions, modify risk...
February 10, 2017: Genes, Brain, and Behavior
https://www.readbyqxmd.com/read/28186680/the-group-ii-metabotropic-glutamate-receptor-agonist-ly354740-and-the-d2-receptor-antagonist-haloperidol-reduce-locomotor-hyperactivity-but-fail-to-rescue-spatial-working-memory-in-glua1-knockout-mice
#15
Thomas Boerner, Alexei Bygrave, Jingkai Chen, Anushka Fernando, Stephanie Jackson, Chris Barkus, Rolf Sprengel, Peter H Seeburg, Paul J Harrison, Gary Gilmour, David M Bannerman, David J Sanderson
Group II metabotropic glutamate receptor agonists have been suggested as potential anti-psychotics, at least in part, based on the observation that the agonist LY354740 appeared to rescue the cognitive deficits caused by non-competitive N-methyl-D-aspartate receptor (NMDAR) antagonists, including spatial working memory deficits in rodents. Here, we tested the ability of LY354740 to rescue spatial working memory performance in mice that lack the GluA1 subunit of the AMPA glutamate receptor, encoded by Gria1, a gene recently implicated in schizophrenia by genome-wide association studies...
February 10, 2017: European Journal of Neuroscience
https://www.readbyqxmd.com/read/28181134/the-effect-and-mechanism-of-dopamine-d1-receptors-on-the-proliferation-of-osteosarcoma-cells
#16
Jun Gao, Chao Zhang, Feng Gao, Hongzhu Li
The physiological and pathological roles of dopamine D1 receptors (DR1) in the regulation of functions in tissues and organs have been recognized. However, whether DR1 are expressed in the osteosarcoma cells and inhibit the proliferation of these cells is unknown. In the present study, we found that DR1 were expressed in the osteosarcoma cells (OS732 cells). SKF-38393 (DR1 agonist) and the overexpression of DR1 decreased the proliferation of OS732 cells; SCH-23390 (DR1 antagonist) and the knockdown of DR1 increased the proliferation of OS732 cells, and both SCH-23390 and the knockdown of DR1 abolished the effect of SKF-38393 on the proliferation of OS732 cells...
February 8, 2017: Molecular and Cellular Biochemistry
https://www.readbyqxmd.com/read/28177981/high-fat-diet-alters-weight-caloric-intake-and-haloperidol-sensitivity-in-the-context-of-effort-based-responding
#17
Stephen H Robertson, Steven R Boomhower, Erin B Rasmussen
High-fat (HF) diets result in weight gain, hyperphagia, and reduced dopamine D2 signaling; however, these findings have been obtained only under free-feeding conditions. This study tested the extent to which HF diet affects effort-dependent food procurement and the extent to which dopamine signaling is involved. Male Sprague-Dawley rats consumed either a HF (n=20) or a standard-chow (n=20) diet. We assessed the sensitivity to effort-based reinforcement in 10 rats from each group by measuring consumption across a series of fixed-ratio schedules (FR 5-FR 300) under a closed economy and quantified performance using the exponential-demand equation...
February 7, 2017: Behavioural Pharmacology
https://www.readbyqxmd.com/read/28177213/characterization-of-optically-and-electrically-evoked-dopamine-release-in-striatal-slices-from-digenic-knock-in-mice-with-dat-driven-expression-of-channelrhodopsin
#18
Brian O'Neill, Jyoti C Patel, Margaret E Rice
Fast-scan cyclic voltammetry (FCV) is an established method to monitor increases in extracellular dopamine (DA) concentration ([DA]o) in the striatum, which is densely innervated by DA axons. Ex vivo brain slice preparations provide an opportunity to identify endogenous modulators of DA release. For these experiments, local electrical stimulation is often used to elicit release of DA, as well as other transmitters, in the striatal microcircuitry; changes in evoked increases in [DA]o after application of a pharmacological agent (e...
February 15, 2017: ACS Chemical Neuroscience
https://www.readbyqxmd.com/read/28176147/antagonism-of-dopamine-d2-receptors-alters-phosphorylation-of-fyn-in-the-rat-medial-prefrontal-cortex
#19
Li-Min Mao, John Q Wang
Several Src family kinase (SFK) members are expressed in the mammalian brain and serve as key kinases in the regulation of a variety of cellular and synaptic events. These SFKs may be subject to the modulation by dopamine, although this topic has been investigated incompletely. In this study, we explored whether dopamine D2 receptors (D2Rs) regulate SFKs in adult rat brains in vivo. We investigated the role of D2Rs in two forebrain areas, the medial prefrontal cortex (mPFC) and hippocampus, since dopamine plays a pivotal role in regulating activity of mPFC and hippocampal neurons and D2Rs are expressed in these regions...
February 7, 2017: Journal of Molecular Neuroscience: MN
https://www.readbyqxmd.com/read/28167638/effects-of-repeated-ropinirole-treatment-on-phencyclidine-induced-hyperlocomotion-prepulse-inhibition-deficits-and-social-avoidance-in-rats
#20
Amanda M Maple, Tanessa Call, Phylicia C Kimmel, Ronald P Hammer
Phencyclidine (PCP), a noncompetitive N-methyl D-aspartate (NMDA) receptor antagonist, provides the most complete pharmacological model of schizophrenia in humans and animals. Acute PCP causes hyperlocomotion, disrupts prepulse inhibition (PPI), and increases social avoidance in rats. We previously showed that repeated treatment with the dopamine (DA) D2-like receptor agonists, quinpirole or ropinirole, prevents agonist-induced PPI disruption. The present study examines whether repeated ropinirole treatment similarly attenuates the effects of PCP in a more complete model of schizophrenia symptoms...
February 6, 2017: Journal of Pharmacology and Experimental Therapeutics
keyword
keyword
64143
1
2
Fetch more papers »
Fetching more papers... Fetching...
Read by QxMD. Sign in or create an account to discover new knowledge that matter to you.
Remove bar
Read by QxMD icon Read
×

Search Tips

Use Boolean operators: AND/OR

diabetic AND foot
diabetes OR diabetic

Exclude a word using the 'minus' sign

Virchow -triad

Use Parentheses

water AND (cup OR glass)

Add an asterisk (*) at end of a word to include word stems

Neuro* will search for Neurology, Neuroscientist, Neurological, and so on

Use quotes to search for an exact phrase

"primary prevention of cancer"
(heart or cardiac or cardio*) AND arrest -"American Heart Association"