phMRI | Page 3

Andrea Edit Édes, Xénia Gonda, György Bagdy, Gabriella Juhász
Many common psychiatric disorders such as depression and anxiety disorders are associated with dysfunction in the monoamine neurotransmission in the central nervous system. However, the investigation of these pathophysiological processes in the human living brain is difficult. In case of functional magnetic resonance imaging (fMRI), a non-invasive method for the examination of brain activity, the activity-inducing stimulus is generally a cognitive psychological test, while during pharmacological magnetic resonance imaging (phMRI) the activation is triggered by a specific pharmacon...
June 2014: Neuropsychopharmacologia Hungarica
Pál Kocsis, István Gyertyán, János Éles, Judit Laszy, Nikolett Hegedűs, Dávid Gajári, Levente Deli, Zsófia Pozsgay, Szabolcs Dávid, Károly Tihanyi
Concordant results of functional magnetic resonance imaging (fMRI) and behavioral tests prove that some non-blood-brain barrier-penetrating drugs produce robust central nervous system (CNS) effects. The anticholinergic scopolamine interferes with learning when tested in rats, which coincides with a negative blood-oxygen-level-dependent (BOLD) change in the prefrontal cortex (PFC) as demonstrated by fMRI. The peripherally acting butylscopolamine also evokes a learning deficit in a water-labyrinth test and provokes a negative BOLD signal in the PFC...
June 2014: Journal of Cerebral Blood Flow and Metabolism
Joseph B Mandeville, Christina H Liu, Wim Vanduffel, John J A Marota, Bruce G Jenkins
Although functional MRI traditionally has been applied mainly to study changes in task-induced brain function, evolving acquisition methodologies and improved knowledge of signal mechanisms have increased the utility of this method for studying responses to pharmacological stimuli, a technique often dubbed "phMRI". The proliferation of higher magnetic field strengths and the use of exogenous contrast agent have boosted detection power, a critical factor for successful phMRI due to the restricted ability to average multiple stimuli within subjects...
September 2014: Neuropharmacology
Nellie E Byun, Michael Grannan, Michael Bubser, Robert L Barry, Analisa Thompson, John Rosanelli, Raajaram Gowrishankar, Nathaniel D Kelm, Stephen Damon, Thomas M Bridges, Bruce J Melancon, James C Tarr, John T Brogan, Malcolm J Avison, Ariel Y Deutch, Jürgen Wess, Michael R Wood, Craig W Lindsley, John C Gore, P Jeffrey Conn, Carrie K Jones
Accumulating evidence suggests that selective M4 muscarinic acetylcholine receptor (mAChR) activators may offer a novel strategy for the treatment of psychosis. However, previous efforts to develop selective M4 activators were unsuccessful because of the lack of M4 mAChR subtype specificity and off-target muscarinic adverse effects. We recently developed VU0152100, a highly selective M4 positive allosteric modulator (PAM) that exerts central effects after systemic administration. We now report that VU0152100 dose-dependently reverses amphetamine-induced hyperlocomotion in rats and wild-type mice, but not in M4 KO mice...
June 2014: Neuropsychopharmacology
Brad Miller, Lauren A Marks, Jonathan M Koller, Blake J Newman, G Larry Bretthorst, Kevin J Black
Background. This study's goal was to provide dose-response data for a dopamine agonist in the baboon using standard methods (replicate measurements at each dose, across a range of doses), as a standard against which to subsequently validate a novel pharmacological MRI (phMRI) method. Dependent variables were functional MRI (fMRI) data from brain regions selected a priori, and systemic prolactin release. Necessary first steps included estimating the magnitude and time course of prolactin response to anesthesia alone and to various doses of agonist...
2013: PeerJ
Pál Kocsis, Dávid Gajári, Levente Deli, Krisztina Zsedrovitsné Gőcze, Zsófia Pozsgay, Károly Tihanyi
Tolperisone is a voltage gated sodium channel blocker, centrally acting muscle relaxant drug, with a very advantageous side effect profile. Like other sodium channel blockers, it has weak affinity to the resting state and high affinity to the open/inactivated state of the channel. In this paper, its effect on BOLD responses in rat brain were elucidated both on the resting brain and paw stimulation evoked BOLD responses. Tolperisone did not exert any visible effect on resting brain, but strongly inhibited the paw stimulation evoked BOLD responses, showing somewhat higher efficacy in brain areas involved in pain sensation...
October 2013: Brain Research Bulletin
Niklaus Denier, Hana Gerber, Marc Vogel, Markus Klarhöfer, Anita Riecher-Rossler, Gerhard A Wiesbeck, Undine E Lang, Stefan Borgwardt, Marc Walter
Heroin dependence is a chronic relapsing brain disorder, characterized by the compulsion to seek and use heroin. Heroin itself has a strong potential to produce subjective experiences characterized by intense euphoria, relaxation and release from craving. The neurofunctional foundations of these perceived effects are not well known. In this study, we have used pharmacological magnetic resonance imaging (phMRI) in 15 heroin-dependent patients from a stable heroin-assisted treatment program to observe the steady state effects of heroin (60 min after administration)...
2013: PloS One
Christoph Kraus, Sebastian Ganger, Jan Losak, Andreas Hahn, Markus Savli, Georg S Kranz, Pia Baldinger, Christian Windischberger, Siegfried Kasper, Rupert Lanzenberger
Preclinical studies have demonstrated that serotonin (5-HT) challenge changes neuronal circuitries and microarchitecture. However, evidence in human subjects is missing. Pharmacologic magnetic resonance imaging (phMRI) applying selective 5-HT reuptake inhibitors (SSRIs) and high-resolution structural and functional brain assessment is able to demonstrate the impact of 5-HT challenge on neuronal network morphology and functional activity. To determine how SSRIs induce changes in gray matter and neuronal activity, we conducted a longitudinal study using citalopram and escitalopram...
January 1, 2014: NeuroImage
B A Hooker, G Tobon, S J Baker, C Zhu, J Hesterman, K Schmidt, R Rajagovindan, P Chandran, S K Joshi, A W Bannon, J Hoppin, J Beaver, G B Fox, M Day, J Upadhyay
BACKGROUND: The function of brain networks can be changed in a maladaptive manner in response to chronic neuropathic pain. Analgesics can reduce pain by acting on such networks via direct or indirect (peripheral or spinal) mechanisms. This investigation aimed to map gabapentin's pharmacodynamics (PD) in the rodent brain following induction of neuropathic pain in order to further understand its PD profile. METHODS: Pharmacological magnetic resonance imaging (phMRI) and a novel functional connectivity analysis procedure were performed following vehicle or gabapentin treatment in the rat spinal nerve ligation (SNL) model of neuropathic pain as well as sham animals...
February 2014: European Journal of Pain: EJP
A Schrantee, L Reneman
Dopamine abnormalities underlie a wide variety of psychopathologies, including ADHD and schizophrenia. A new imaging technique, pharmacological magnetic resonance imaging (phMRI), is a promising non-invasive technique to visualize the dopaminergic system in the brain. In this review we explore the clinical potential of phMRI in detecting dopamine dysfunction or neurotoxicity, assess its strengths and weaknesses and identify directions for future research. Preclinically, phMRI is able to detect severe dopaminergic abnormalities quite similar to conventional techniques such as PET and SPECT...
September 2014: Neuropharmacology
Brian V Broberg, Kristoffer H Madsen, Niels Plath, Christina K Olsen, Birte Y Glenthøj, Olaf B Paulson, Börje Bjelke, Lise V Søgaard
Better animal models are needed to aid the development of new medications to alleviate the cognitive deficits associated with schizophrenia. Growing evidence suggests neurodevelopmental insults and disturbances in NMDA receptor (NMDAR) signaling to be involved in the schizophrenia etiology. Acute administration of phencyclidine (PCP) induces schizophrenia-like symptoms in healthy volunteers and exacerbates symptoms in patients with schizophrenia. In this study, pharmacological Magnetic Resonance Imaging (phMRI) was used to evaluate if rats treated with 20mg/kg PCP on postnatal days 7, 9, and 11 (neoPCP), compared to saline (neoVeh), were hypersensitive to acute PCP administration in adulthood (acutePCP)...
August 1, 2013: Behavioural Brain Research
A Klomp, G A van Wingen, M B de Ruiter, M W A Caan, D Denys, L Reneman
Non-invasive assessment of human neurotransmitter function is a highly valuable tool in clinical research. Despite the current interest in task-based pharmacological MRI (phMRI) for the assessment of neural correlates of serotonin (5-HT) function, test-retest reliability of this technique has not yet been established. Using a placebo-controlled crossover design, we aimed to examine the repeatability of task-related phMRI with a single dose of oral citalopram in twelve healthy female subjects. Since we were interested in the drug's effect on neural correlates of 5-HT related cognitive processes, a sensorimotor and an emotional face processing paradigm were used...
July 15, 2013: NeuroImage
Gerard B Fox, Steve McGaraughty, Yanping Luo
Functional magnetic resonance imaging (fMRI) has transformed cognitive neuroscience over the past 10 - 15 years, allowing clinical researchers unprecedented access to the functioning of the human brain under many different conditions including motor, sensory and cognitive stimulation. During the past 5 years, increasing interest has also focused on mapping pharmacologically induced changes in human brain activity produced following exposure to psychoactive agents such as amphetamine and cocaine, and is now frequently termed pharmacological MRI (phMRI)...
August 2006: Expert Opinion on Drug Discovery
Yvonne Couch, Chris J Martin, Clare Howarth, Josie Raley, Alexandre A Khrapitchev, Michael Stratford, Trevor Sharp, Nicola R Sibson, Daniel C Anthony
Considerable evidence indicates a link between systemic inflammation and central 5-HT function. This study used pharmacological magnetic resonance imaging (phMRI) to study the effects of systemic inflammatory events on central 5-HT function. Changes in blood oxygenation level dependent (BOLD) contrast were detected in selected brain regions of anaesthetised rats in response to intravenous administration of the 5-HT-releasing agent, fenfluramine (10 mg/kg). Further groups of rats were pre-treated with the bacterial lipopolysaccharide (LPS; 0...
July 15, 2013: NeuroImage
M L J Schouw, M W A Caan, H M Geurts, B Schmand, J Booij, A J Nederveen, L Reneman
Preclinical studies suggest that dexamphetamine (dAMPH) can lead to monoaminergic neurotoxicity. This exploratory study aimed to investigate effects of recreational dAMPH use on the dopamine (DA) and noradrenaline (NA) systems in humans. To that purpose, eight male abstinent dAMPH (26.0 ± 4.0 years) users and 10 age- and IQ-matched male healthy control subjects (23.0 ± 3.8) underwent neuropsychological testing sensitive to DAergic function and single photon emission computed tomography (SPECT) scanning with [(123)I]FP-CIT to determine striatal DA transporter (DAT) binding...
November 2013: European Neuropsychopharmacology: the Journal of the European College of Neuropsychopharmacology
Lino Becerra, Jaymin Upadhyay, Pei-Ching Chang, James Bishop, Julie Anderson, Richard Baumgartner, Adam J Schwarz, Alexandre Coimbra, Diana Wallin, Lauren Nutile, Edward George, Gary Maier, Soujanya Sunkaraneni, Smriti Iyengar, Jeffrey L Evelhoch, David Bleakman, Richard Hargreaves, David Borsook
Pharmacological magnetic resonance imaging (phMRI) is one method by which a drug's pharmacodynamic effects in the brain can be assessed. Although phMRI has been frequently used in preclinical and clinical settings, the extent to which a phMRI signature for a compound translates between rodents and humans has not been systematically examined. In the current investigation, we aimed to build on recent clinical work in which the functional response to 0.1 and 0.2 mg/70 kg i.v. buprenorphine (partial µ-opioid receptor agonist) was measured in healthy humans...
April 2013: Journal of Pharmacology and Experimental Therapeutics
O M Doyle, S De Simoni, A J Schwarz, C Brittain, O G O'Daly, S C R Williams, M A Mehta
Ketamine acts as an N-methyl-D-aspartate receptor antagonist and evokes psychotomimetic symptoms resembling schizophrenia in healthy humans. Imaging markers of acute ketamine challenge have the potential to provide a powerful assay of novel therapies for psychiatric illness, although to date this assay has not been fully validated in humans. Pharmacological magnetic resonance imaging (phMRI) was conducted in a randomized, placebo-controlled crossover design in healthy volunteers. The study comprised a control and three ketamine infusion sessions, two of which included pretreatment with lamotrigine or risperidone, compounds hypothesized to reduce ketamine-induced glutamate release...
April 2013: Journal of Pharmacology and Experimental Therapeutics
S Sekar, E Jonckers, M Verhoye, R Willems, J Veraart, J Van Audekerke, J Couto, M Giugliano, K Wuyts, S Dedeurwaerdere, J Sijbers, C Mackie, L Ver Donck, T Steckler, A Van der Linden
BACKGROUND: An effective NMDA antagonist imaging model may find key utility in advancing schizophrenia drug discovery research. We investigated effects of subchronic treatment with the NMDA antagonist memantine by using behavioural observation and multimodal MRI. METHODS: Pharmacological MRI (phMRI) was used to map the neuroanatomical binding sites of memantine after acute and subchronic treatment. Resting state fMRI (rs-fMRI) and diffusion MRI were used to study the changes in functional connectivity (FC) and ultra-structural tissue integrity before and after subchronic memantine treatment...
June 2013: Psychopharmacology
Robert Gear, Lino Becerra, Jaymin Upadhyay, James Bishop, Diana Wallin, Gautam Pendse, Jon Levine, David Borsook
Nalbuphine, an agonist-antagonist kappa-opioid, produces brief analgesia followed by enhanced pain/hyperalgesia in male postsurgical patients. However, it produces profound analgesia without pain enhancement when co-administration with low dose naloxone. To examine the effect of nalbuphine or nalbuphine plus naloxone on activity in brain regions that may explain these differences, we employed pharmacological magnetic resonance imaging (phMRI) in a double blind cross-over study with 13 healthy male volunteers...
2013: PloS One
M L J Schouw, A M Kaag, M W A Caan, D F R Heijtel, C B L M Majoie, A J Nederveen, J Booij, L Reneman
Pharmacological magnetic resonance imaging (phMRI) maps the neurovascular response to a pharmacological challenge and is increasingly used to assess neurotransmitter systems. Here we investigated the hemodynamic response to a dopaminergic (DAergic) challenge with dextroamphetamine (dAMPH) in humans using arterial spin labeling (ASL) based phMRI. Twelve healthy male subjects aged 21.0years (±1.5) were included. We used a pseudo-continuous ASL sequence (40min) to quantify cerebral blood flow (CBF) and started dAMPH infusion (0...
May 15, 2013: NeuroImage
Fetch more papers »
Fetching more papers... Fetching...
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"