• Login
    View Item 
    •   Home
    • Graduate Theses, Dissertations and Projects
    • Queen's Graduate Theses and Dissertations
    • View Item
    •   Home
    • Graduate Theses, Dissertations and Projects
    • Queen's Graduate Theses and Dissertations
    • View Item
    JavaScript is disabled for your browser. Some features of this site may not work without it.

    mTOR Pathway is Up-regulated by Both Acute Endurance Exercise and Chronic Muscle Contraction in Rat Skeletal Muscle

    Thumbnail
    View/Open
    Edgett_Brittany_A_201209_MSc.pdf (1.673Mb)
    Date
    2012-10-04
    Author
    Edgett, Brittany
    Metadata
    Show full item record
    Abstract
    The purpose of this thesis was to examine changes in the expression of translation regulatory proteins following both an acute bout of endurance exercise and chronic muscle contractile activity. In experiment 1, female Sprague-Dawley rats ran for 2 h at 15 m/min followed by an increase in speed of 5 m/min every 5 min until volitional fatigue. Red gastrocnemius muscle was harvested from non-exercised animals (control), immediately following cessation of exercise (0 h) and after 3 hours of recovery (3 h). Compared to control, rpS6 mRNA was elevated (p < .05) at both 0 h (+32%) and 3 h (+47%). Both eIF2Bε (+127%) and mTOR mRNA (+44%) were higher than control at 3 h, while eIF4E decreased (-24%) immediately following exercise (p < .05). Phosphorylation of mTOR (+40%) and S6K1 (+266%) also increased immediately post-exercise (p < .05). In experiment 2, female Sprague-Dawley rats underwent chronic stimulation of the peroneal nerve continuously for 7 days. The red gastrocnemius muscle was removed 24 h following cessation of the stimulation. Chronic muscle stimulation up-regulated (P < .05) mTOR protein (+74%), rpS6 (+31%), and eIF2α (+44%, P < .07), and this was accompanied by an increase in cytochrome C (+31%). Phosphorylation of rpS6 (Ser235/Ser236) was increased (+51%, P < .05), while mTOR (Ser2448) and 4E-BP1 (Thr37/46) did not change. These experiments demonstrate that acute and chronic endurance contractile activity up-regulate the mTOR signalling pathway and mitochondrial content in murine skeletal muscle. This up-regulation of the mTOR pathway may increase translation efficiency and may also represent an important control point in exercise mediated mitochondrial biogenesis.
    URI for this record
    http://hdl.handle.net/1974/7576
    Collections
    • Queen's Graduate Theses and Dissertations
    • School of Kinesiology & Health Studies Graduate Theses
    Request an alternative format
    If you require this document in an alternate, accessible format, please contact the Queen's Adaptive Technology Centre

    DSpace software copyright © 2002-2015  DuraSpace
    Contact Us
    Theme by 
    Atmire NV
     

     

    Browse

    All of QSpaceCommunities & CollectionsPublished DatesAuthorsTitlesSubjectsTypesThis CollectionPublished DatesAuthorsTitlesSubjectsTypes

    My Account

    LoginRegister

    Statistics

    View Usage StatisticsView Google Analytics Statistics

    DSpace software copyright © 2002-2015  DuraSpace
    Contact Us
    Theme by 
    Atmire NV