• Login
    View Item 
    •   UMB Digital Archive
    • School, Graduate
    • Theses and Dissertations All Schools
    • View Item
    •   UMB Digital Archive
    • School, Graduate
    • Theses and Dissertations All Schools
    • View Item
    JavaScript is disabled for your browser. Some features of this site may not work without it.

    Browse

    All of UMB Digital ArchiveCommunitiesPublication DateAuthorsTitlesSubjectsThis CollectionPublication DateAuthorsTitlesSubjects

    My Account

    LoginRegister

    Statistics

    Display statistics

    Interactive effects of MK-801 and morphine on EEG, EEG power spectra and behavior in rats: Acute, tolerance and dependence studies

    • CSV
    • RefMan
    • EndNote
    • BibTex
    • RefWorks
    Find Full text
    Author
    Haberny, Kathleen Anne Y.
    Advisor
    Young, Gerald A.
    Date
    1993
    Type
    dissertation
    
    Metadata
    Show full item record
    Abstract
    Recent studies investigated an interaction between MK-801 and morphine-induced analgesia which originates in spinal and supraspinal subcortical areas of the CNS, particularly in the periaqueductal gray. Interactive effects between MK-801 and morphine-induced cortical EEG that coincides with behavior generated in mesolimbic areas have not been demonstrated. The present study first investigated an acute interaction between MK-801 and morphine-induced effects on cortical EEG and EEG spectral parameters in rat. Rats were administered one of five doses of MK-801 (0.003-0.3 mg/kg, i.p.) prior to morphine (3 mg/kg, i.v.), or MK-801 (0.1 mg/kg, i.p.) prior to an increasing cumulative morphine dose over a period of 120 minutes (5-120 mg/kg, i.v.). MK-801 pretreatment produced a significant dose-response effect and increased morphine-induced global spectral power (mV{dollar}\sp2{dollar}/Hz), duration of morphine-induced high voltage slow wave EEG bursts and latency to sleep onset. MK-801 significantly decreased morphine-induced mean frequency, mobility, complexity and edge frequency, and shifted the relative distribution of total power as a function of frequency band to lower frequencies, increasing power in the 0-5 Hz range. Significant interaction effects were found for all spectral parameters except peak frequency. Pretreatment with MK-801 shifted the cumulative morphine dose-response curve for total power to the left and for complexity to the right. The results demonstrated that MK-801 potentiates morphine-induced effects on EEG and EEG spectral parameters quantitatively in rat brain and produces qualitative changes in the EEG response to morphine. A potential interaction between MK-801 and morphine tolerance and dependence was further investigated. Rats were treated for seven days with morphine alone or with morphine and MK-801. Control groups received chronic MK-801 alone or saline. On day eight all rats received morphine alone followed by naloxone. An additional group received chronic morphine alone, followed by MK-801 on day eight prior to morphine and naloxone. Co-treatment significantly accelerated the development of tolerance to morphine-induced total power and latency to sleep onset. MK-801 co-treatment decreased, where chronic morphine alone increased, the excitatory response to morphine. Chronic co-administration had no effect on the EEG and behavioral response to naloxone precipitated morphine withdrawal, but acute MK-801 in morphine tolerant animals prevented the behavioral signs of morphine withdrawal. The results support recent reports that chronic morphine treatment produces supersensitivity to glutamate in the rat cortex and alteration in mesolimbic dopamine levels which are modulated by glutaminergic activity. In conclusion, acute co-treatment with MK-801 significantly potentiates morphine-induced EEG, EEG spectral parameters and behavior, and attenuates the behavioral signs of withdrawal from morphine following chronic morphine administration. Chronic co-treatment, furthermore, accelerates the development of tolerance to morphine-induced effects on these parameters.
    Description
    University of Maryland, Baltimore. Ph.D. 1993
    Keyword
    Biology, Neuroscience
    Health Sciences, Pharmacology
    Identifier to cite or link to this item
    http://hdl.handle.net/10713/1641
    Collections
    Theses and Dissertations All Schools
    Theses and Dissertations School of Pharmacy

    entitlement

     
    DSpace software (copyright © 2002 - 2021)  DuraSpace
    Quick Guide | Policies | Contact Us | UMB Health Sciences & Human Services Library
    Open Repository is a service operated by 
    Atmire NV
     

    Export search results

    The export option will allow you to export the current search results of the entered query to a file. Different formats are available for download. To export the items, click on the button corresponding with the preferred download format.

    By default, clicking on the export buttons will result in a download of the allowed maximum amount of items.

    To select a subset of the search results, click "Selective Export" button and make a selection of the items you want to export. The amount of items that can be exported at once is similarly restricted as the full export.

    After making a selection, click one of the export format buttons. The amount of items that will be exported is indicated in the bubble next to export format.