• Libraries
    • Log in to:
    View Item 
    •   MSpace Home
    • Faculty of Graduate Studies (Electronic Theses and Practica)
    • FGS - Electronic Theses and Practica
    • View Item
    •   MSpace Home
    • Faculty of Graduate Studies (Electronic Theses and Practica)
    • FGS - Electronic Theses and Practica
    • View Item
    JavaScript is disabled for your browser. Some features of this site may not work without it.

    Characterization of bidirectional adenosine transporters in rat brain synaptosomes and clonal DDT|1 MF-2 smooth muscle cells using [3H]L-adenosine

    Thumbnail
    View/Open
    mq23305.pdf (4.412Mb)
    Date
    1997-05-01
    Author
    Foga, Irene Oksana
    Metadata
    Show full item record
    Abstract
    Membrane-bound nucleoside transport processes and their inhibitors regulate intra- and extra-cellular levels of endogenous D-adenosine and the actions of adenosine are mediated through adenosine receptors. Our research involved (1) developing a method to measure adenosine transport and release in animal cells and CNS tissue, (2) characterizing the transport processes involved, and (3) determining the effects of transport inhibitors on these processes. Using rat brain synaptosomal preparations we showed that ($\sp3$H) L-adenosine, the metabolically stable enantiomer of ($\sp3$H) D-adenosine, was released in a concentration- and time-dependent, and temperature-sensitive manner that was linear with synaptosomal protein content. Release of ($\sp3$H) L-adenosine was inhibited by the nucleoside transport inhibitors dipyridamole, nitrobenzylthioinosine (NBI) and dilazep, as well as unlabelled L-adenosine, D-adenosine and uridine, suggesting that release occurred at least in part by NBI-sensitive equilibrative nucleoside transporters. To determine further which subtype of equilibrative nucleoside transporter was involved, we conducted similar studies using cells, DDT$\sb1$ MF-2 cells, that contain only NBI-sensitive (es) nucleoside transporters. In DDT$\sb1$ MF-2 cells, accumulation of ($\sp3$H) D-adenosine was more rapid than that of ($\sp3$H) L-adenosine. ($\sp3$H) D-Adenosine uptake was inhibited by unlabelled L-adenosine to a greater degree than ($\sp3$H) L-adenosine uptake was inhibited by unlabelled D-adenosine. Nitrobenzylthioinosine inhibited uptake of ($\sp3$H) D- and ($\sp3$H) L-adenosine. ($\sp3$H) L-Adenosine release was temperature- and time-dependent, and was inhibited by NBI. Our studies support the use of ($\sp3$H) L-adenosine as a useful probe for the characterization adenosine transport and release, and show that release occurs in part by nucleoside transporters that are sensitive to inhibition by nanomolar concentrations of NBI. Such studies may help identify therapeutically useful adenosine transport inhibitors.
    URI
    http://hdl.handle.net/1993/936
    Collections
    • FGS - Electronic Theses and Practica [25494]

    DSpace software copyright © 2002-2016  DuraSpace
    Contact Us | Send Feedback
    Theme by 
    Atmire NV
     

     

    Browse

    All of MSpaceCommunities & CollectionsBy Issue DateAuthorsTitlesSubjectsThis CollectionBy Issue DateAuthorsTitlesSubjects

    My Account

    Login

    Statistics

    View Usage Statistics

    DSpace software copyright © 2002-2016  DuraSpace
    Contact Us | Send Feedback
    Theme by 
    Atmire NV