The Experts below are selected from a list of 171 Experts worldwide ranked by ideXlab platform

Jose A Moron - One of the best experts on this subject based on the ideXlab platform.

  • modulation of opiate related signaling molecules in morphine dependent Conditioned Behavior Conditioned place preference to morphine induces creb phosphorylation
    Neuropsychopharmacology, 2010
    Co-Authors: Jose A Moron, Srinivas Gullapalli, Chirisse Taylor, Achla Gupta, Ivone Gomes, Lakshmi A Devi
    Abstract:

    Opiate addiction is a chronic, relapsing Behavioral disorder where learned associations that develop between the abused opiate and the environment in which it is consumed are brought about through Pavlovian (classical) conditioning processes. However, the signaling mechanisms/pathways regulating the mechanisms that underlie the responses to opiate-associated cues or the development of sensitization as a consequence of repeated context-independent administration of opiates are unknown. In this study we examined the phosphorylation levels of various classic signaling molecules in brain regions implicated in addictive Behaviors after acute and repeated morphine administration. An unbiased place conditioning protocol was used to examine changes in phosphorylation that are associated with (1) the expression of the rewarding effects of morphine and (2) the sensitization that develops to this effect. We also examined the effects of a δ-receptor antagonist on morphine-induced Conditioned Behavior and on the phosphorylation of classic signaling molecules in view of data showing that blockade of δ-opioid receptor (δOR) prevents the development of sensitization to the rewarding effects of morphine. We find that CREB phosphorylation is specifically induced upon the expression of a sensitized response to morphine-induced Conditioned Behavior in brain areas related to memory consolidation, such as the hippocampus and cortex. A similar effect is also observed, albeit to a lesser extent, in the case of the GluR1 subunit of AMPA glutamate receptor. These increases in the phosphorylation levels of CREB and pGluR1 are significantly blocked by pretreatment with a δOR antagonist. These results indicate a critical role for phospho-CREB, AMPA, and δOR activities in mediating the expression of a sensitized response to morphine-dependent Conditioned Behavior.

  • extinction of morphine dependent Conditioned Behavior is associated with increased phosphorylation of the glur1 subunit of ampa receptors at hippocampal synapses
    European Journal of Neuroscience, 2009
    Co-Authors: Sophie K Billa, Namita Sinha, Sri Rajyalakshmi Rudrabhatla, Jose A Moron
    Abstract:

    In abstinent opiate addicts, relapse can be triggered by exposure to environmental cues associated with drug use; thus, the disruption of these learned associations may be an effective approach for reducing relapse. Interestingly, glutamatergic systems are thought to be involved in opiate-induced Behavioral plasticity. In this study, changes in expression and phosphorylation levels of AMPA glutamate receptor subunits (GluR1, GluR2) in the hippocampus were investigated in rats showing a Conditioned response to an opiate-paired environment as well as in animals in which this Conditioned Behavior was extinguished. Additionally, another set of animals went through a drug-unpaired paradigm (without conditioning) in order to examine the effects of the pharmacology of the drug itself. Subcellular fractionation techniques were used to analyze the local distribution of AMPA glutamate subunits within the synapse, especially at the postsynaptic density (PSD). Results showed that morphine-dependent Conditioned responses did not alter expression or redistribution of GluR1 or GluR2; however the unpaired administration of morphine resulted in an increase in the phosphorylation of the GluR1 subunit at extrasynaptic sites. Interestingly, the extinction of the Conditioned response significantly increased phosphorylation of the GluR1 subunit at the PSD. Therefore we propose that, within the synapse, the phosphorylation of the GluR1 subunit at the PSD may be a key mechanism in the extinction of opiate-associated Conditioned responses.

  • Extinction of morphine-dependent Conditioned Behavior is associated with increased phosphorylation of the GluR1 subunit of AMPA receptors at hippocampal synapses.
    European Journal of Neuroscience, 2008
    Co-Authors: Sophie K Billa, Namita Sinha, Sri Rajyalakshmi Rudrabhatla, Jose A Moron
    Abstract:

    In abstinent opiate addicts, relapse can be triggered by exposure to environmental cues associated with drug use; thus, the disruption of these learned associations may be an effective approach for reducing relapse. Interestingly, glutamatergic systems are thought to be involved in opiate-induced Behavioral plasticity. In this study, changes in expression and phosphorylation levels of alpha-amino-3-hydroxy-5-methyl-4-isoxazolepropionic acid (AMPA) glutamate receptor subunits (GluR1, GluR2) in the hippocampus were investigated in rats showing a Conditioned response (CR) to an opiate-paired environment as well as in animals in which this Conditioned Behavior was extinguished. Additionally, another set of animals went through a drug-unpaired paradigm (without conditioning) in order to examine the effects of the pharmacology of the drug itself. Subcellular fractionation techniques were used to analyse the local distribution of AMPA glutamate subunits within the synapse, especially at the postsynaptic density (PSD). Results showed that morphine-dependent CRs did not alter expression or redistribution of GluR1 or GluR2; however, the unpaired administration of morphine resulted in an increase in the phosphorylation of the GluR1 subunit at extrasynaptic sites. Interestingly, the extinction of the CR significantly increased phosphorylation of the GluR1 subunit at the PSD. Therefore we propose that, within the synapse, the phosphorylation of the GluR1 subunit at the PSD may be a key mechanism in the extinction of opiate-associated CRs.

Lakshmi A Devi - One of the best experts on this subject based on the ideXlab platform.

  • modulation of opiate related signaling molecules in morphine dependent Conditioned Behavior Conditioned place preference to morphine induces creb phosphorylation
    Neuropsychopharmacology, 2010
    Co-Authors: Jose A Moron, Srinivas Gullapalli, Chirisse Taylor, Achla Gupta, Ivone Gomes, Lakshmi A Devi
    Abstract:

    Opiate addiction is a chronic, relapsing Behavioral disorder where learned associations that develop between the abused opiate and the environment in which it is consumed are brought about through Pavlovian (classical) conditioning processes. However, the signaling mechanisms/pathways regulating the mechanisms that underlie the responses to opiate-associated cues or the development of sensitization as a consequence of repeated context-independent administration of opiates are unknown. In this study we examined the phosphorylation levels of various classic signaling molecules in brain regions implicated in addictive Behaviors after acute and repeated morphine administration. An unbiased place conditioning protocol was used to examine changes in phosphorylation that are associated with (1) the expression of the rewarding effects of morphine and (2) the sensitization that develops to this effect. We also examined the effects of a δ-receptor antagonist on morphine-induced Conditioned Behavior and on the phosphorylation of classic signaling molecules in view of data showing that blockade of δ-opioid receptor (δOR) prevents the development of sensitization to the rewarding effects of morphine. We find that CREB phosphorylation is specifically induced upon the expression of a sensitized response to morphine-induced Conditioned Behavior in brain areas related to memory consolidation, such as the hippocampus and cortex. A similar effect is also observed, albeit to a lesser extent, in the case of the GluR1 subunit of AMPA glutamate receptor. These increases in the phosphorylation levels of CREB and pGluR1 are significantly blocked by pretreatment with a δOR antagonist. These results indicate a critical role for phospho-CREB, AMPA, and δOR activities in mediating the expression of a sensitized response to morphine-dependent Conditioned Behavior.

Ken Lukowiak - One of the best experts on this subject based on the ideXlab platform.

  • changes in the activity of a cpg neuron after the reinforcement of an operantly Conditioned Behavior in lymnaea
    Journal of Neurophysiology, 2002
    Co-Authors: Gaynor E Spencer, Mustapha H Kazmi, Naweed I Syed, Ken Lukowiak
    Abstract:

    We have previously shown that the aerial respiratory Behavior of the molluskLymnaea stagnalis can be operantly Conditioned, and the central pattern generating (CPG) neurons underlying this Behavior have been identified. As neural correlates of operant conditioning remain poorly defined in both vertebrates and invertebrates, we have used theLymnaea respiratory CPG to investigate neuronal changes associated with the change in Behavior after conditioning. After operant conditioning of the intact animals, semi-intact preparations were dissected, so that changes in the respiratory Behavior (pneumostome openings) and underlying activity of the identified CPG neuron, right pedal dorsal 1 (RPeD1), could be monitored simultaneously. RPeD1 was studied because it initiates the rhythmic activity of the CPG and receives chemo-sensory input from the pneumostome area. Pneumostome openings and RPeD1 activity were monitored both before and after a reinforcing training stimulus applied to the open pneumostome of operantly ...

  • Changes in the activity of a CpG neuron after the reinforcement of an operantly Conditioned Behavior in Lymnaea.
    Journal of Neurophysiology, 2002
    Co-Authors: Gaynor E Spencer, Mustapha H Kazmi, Naweed I Syed, Ken Lukowiak
    Abstract:

    We have previously shown that the aerial respiratory Behavior of the mollusk Lymnaea stagnalis can be operantly Conditioned, and the central pattern generating (CPG) neurons underlying this Behavior have been identified. As neural correlates of operant conditioning remain poorly defined in both vertebrates and invertebrates, we have used the Lymnaea respiratory CPG to investigate neuronal changes associated with the change in Behavior after conditioning. After operant conditioning of the intact animals, semi-intact preparations were dissected, so that changes in the respiratory Behavior (pneumostome openings) and underlying activity of the identified CPG neuron, right pedal dorsal 1 (RPeD1), could be monitored simultaneously. RPeD1 was studied because it initiates the rhythmic activity of the CPG and receives chemo-sensory input from the pneumostome area. Pneumostome openings and RPeD1 activity were monitored both before and after a reinforcing training stimulus applied to the open pneumostome of operantly Conditioned and yoked control preparations. After presentation of the reinforcing stimulus, there was a significant reduction in both breathing Behavior and RPeD1 activity in operant preparations but not in yoked and naive controls. Furthermore these changes were only significant in the subgroup of operantly Conditioned animals described as good learners and not in poor learners. These data strongly suggest that changes in RPeD1 activity may underlie the Behavioral changes associated with the reinforcement of operant conditioning of the respiratory Behavior.

Michael Domjan - One of the best experts on this subject based on the ideXlab platform.

  • General Process Learning Theory: Challenges from Response and Stimulus Factors
    International Journal of Comparative Psychology, 2000
    Co-Authors: Michael Domjan
    Abstract:

    Traditionally, general theories of learning have focused on associative and other mechanisms that are responsible for Conditioned Behavior without seriously considering how those mechanisms might vary depending on the stimulus being learned about and the response that provides evidence of learning. Recent studies of sexual conditioning in male domesticated quail have revealed both quantitative and qualitative variations in the functional properties of Conditioned Behavior depending on the response that is measured and the events or objects that serve as Conditioned stimuli. For example, sexually Conditioned sign tracking Behavior is directly related to the ratio between context exposure (C) and trial duration (T) in a conditioning procedure, but sexually Conditioned goal tracking is inversely related to the C/T ratio. Other studies have shown that Conditioned stimuli that include limited cues from a female quail support different forms of sexually Conditioned Behavior than Conditioned stimuli that lack female features. Furthermore, these various Conditioned responses are differentially sensitive to extinction and reinforcer devaluation. The implications of these findings for general process learning theory are discussed.

  • General Process Learning Theory: Challenges from Response and Stimulus Factors - eScholarship
    International Journal of Comparative Psychology, 2000
    Co-Authors: Michael Domjan
    Abstract:

    Traditionally, general theories of learning have focused on associative and other mechanisms that are responsible for Conditioned Behavior without seriously considering how those mechanisms might vary depending on the stimulus being learned about and the response that provides evidence of learning. Recent studies of sexual conditioning in male domesticated quail have revealed both quantitative and qualitative variations in the functional properties of Conditioned Behavior depending on the response that is measured and the events or objects that serve as Conditioned stimuli. For example, sexually Conditioned sign tracking Behavior is directly related to the ratio between context exposure (C) and trial duration (T) in a conditioning procedure, but sexually Conditioned goal tracking is inversely related to the C/T ratio. Other studies have shown that Conditioned stimuli that include limited cues from a female quail support different forms of sexually Conditioned Behavior than Conditioned stimuli that lack female features. Furthermore, these various Conditioned responses are differentially sensitive to extinction and reinforcer devaluation. The implications of these findings for general process learning theory are discussed.

  • Differences in the sexual Conditioned Behavior of male and female Japanese quail (Coturnix japonica).
    Journal of Comparative Psychology, 1997
    Co-Authors: German Gutierrez, Michael Domjan
    Abstract:

    The Conditioned responses of male and female Japanese quail (Coturnix japonica) were compared in a Pavlovian conditioning procedure in which presentation of a brief Conditioned stimulus was immediately followed by the release of a copulation partner. Male quail vigorously approached the Conditioned stimulus and were much more likely to enter the compartment housing their copulation partner than were female birds (Experiment 1). In females, sexual conditioning resulted in increased squatting (Experiment 2). This response was the reflection of sexual Behavior rather than more general social Behavior (Experiment 3). These findings provide the first definitive evidence of sexual learning in female quail and are consistent with the interpretation that sexual conditioning increases sexual arousal or receptivity in both sexes but the increase has different Behavioral manifestations in male and female quail.

  • topography of sexually Conditioned Behavior in male japanese quail coturnix japonica depends on the cs us interval
    Journal of Experimental Psychology: Animal Behavior Processes, 1994
    Co-Authors: Chana K Akins, Michael Domjan, German Gutierrez
    Abstract:

    : The interval between exposure to a Conditioned stimulus (CS) to male quail and access to a female (the unConditioned stimulus [US]) was varied from 0.5 to 20 min using a Pavlovian delayed conditioning procedure. Increasing the CS-US interval altered the spatial distribution of sexual Conditioned Behavior. With a short CS-US interval (1 min), conditioning resulted in the Ss remaining close to the CS and increasing their locomotor Behavior near the CS. With a long CS-US interval (20 min), the Ss approached the CS to some degree, but their locomotor Behavior was increased in areas further removed from the CS. Results are interpreted within the context of a Behavior systems approach to the study of learning and indicate that the typical finding of an inverse relation between Conditioned responding and the CS-US interval may be an artifact of the use of a limited range of Behavioral measures.

Sophie K Billa - One of the best experts on this subject based on the ideXlab platform.

  • extinction of morphine dependent Conditioned Behavior is associated with increased phosphorylation of the glur1 subunit of ampa receptors at hippocampal synapses
    European Journal of Neuroscience, 2009
    Co-Authors: Sophie K Billa, Namita Sinha, Sri Rajyalakshmi Rudrabhatla, Jose A Moron
    Abstract:

    In abstinent opiate addicts, relapse can be triggered by exposure to environmental cues associated with drug use; thus, the disruption of these learned associations may be an effective approach for reducing relapse. Interestingly, glutamatergic systems are thought to be involved in opiate-induced Behavioral plasticity. In this study, changes in expression and phosphorylation levels of AMPA glutamate receptor subunits (GluR1, GluR2) in the hippocampus were investigated in rats showing a Conditioned response to an opiate-paired environment as well as in animals in which this Conditioned Behavior was extinguished. Additionally, another set of animals went through a drug-unpaired paradigm (without conditioning) in order to examine the effects of the pharmacology of the drug itself. Subcellular fractionation techniques were used to analyze the local distribution of AMPA glutamate subunits within the synapse, especially at the postsynaptic density (PSD). Results showed that morphine-dependent Conditioned responses did not alter expression or redistribution of GluR1 or GluR2; however the unpaired administration of morphine resulted in an increase in the phosphorylation of the GluR1 subunit at extrasynaptic sites. Interestingly, the extinction of the Conditioned response significantly increased phosphorylation of the GluR1 subunit at the PSD. Therefore we propose that, within the synapse, the phosphorylation of the GluR1 subunit at the PSD may be a key mechanism in the extinction of opiate-associated Conditioned responses.

  • Extinction of morphine-dependent Conditioned Behavior is associated with increased phosphorylation of the GluR1 subunit of AMPA receptors at hippocampal synapses.
    European Journal of Neuroscience, 2008
    Co-Authors: Sophie K Billa, Namita Sinha, Sri Rajyalakshmi Rudrabhatla, Jose A Moron
    Abstract:

    In abstinent opiate addicts, relapse can be triggered by exposure to environmental cues associated with drug use; thus, the disruption of these learned associations may be an effective approach for reducing relapse. Interestingly, glutamatergic systems are thought to be involved in opiate-induced Behavioral plasticity. In this study, changes in expression and phosphorylation levels of alpha-amino-3-hydroxy-5-methyl-4-isoxazolepropionic acid (AMPA) glutamate receptor subunits (GluR1, GluR2) in the hippocampus were investigated in rats showing a Conditioned response (CR) to an opiate-paired environment as well as in animals in which this Conditioned Behavior was extinguished. Additionally, another set of animals went through a drug-unpaired paradigm (without conditioning) in order to examine the effects of the pharmacology of the drug itself. Subcellular fractionation techniques were used to analyse the local distribution of AMPA glutamate subunits within the synapse, especially at the postsynaptic density (PSD). Results showed that morphine-dependent CRs did not alter expression or redistribution of GluR1 or GluR2; however, the unpaired administration of morphine resulted in an increase in the phosphorylation of the GluR1 subunit at extrasynaptic sites. Interestingly, the extinction of the CR significantly increased phosphorylation of the GluR1 subunit at the PSD. Therefore we propose that, within the synapse, the phosphorylation of the GluR1 subunit at the PSD may be a key mechanism in the extinction of opiate-associated CRs.