• 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

    Calcium transport in intact mammalian fast-twitch and slow-twitch skeletal muscle fibers

    • CSV
    • RefMan
    • EndNote
    • BibTex
    • RefWorks
    Find Full text
    Author
    Carroll, Stefanie Leigh
    Advisor
    Schneider, Martin F.
    Date
    1996
    Type
    dissertation
    
    Metadata
    Show full item record
    Abstract
    Calcium ions that are released from the Sarcoplasmic Reticulum (SR) upon electrical stimulation bind to troponin C of the thin filament structure, and initiate contraction of the skeletal muscle fiber. In order for the muscle fiber to relax, calcium must dissociate from troponin C and be removed from the cytoplasm by reuptake via the SR Calcium ATPase or by binding to cytoplasmic proteins. The intricacies of the calcium removal system in intact mammalian fibers have not been elucidated. The goal of my thesis project was to characterize the calcium removal system in mammalian intact skeletal muscle fibers, and determine the contribution of the individual components involved, such as the SR calcium ATPase, troponin C, and parvalbumin. Rat fast-twitch flexor digitorum brevis fibers (FDB) and slow-twitch soleus fibers are enzymatically dissociated and suspended in low melting temperature agarose gel to minimize fiber movement during fluorescence recordings. FDB fibers and soleus fibers are loaded with fura-2 (cell permeant form) and electrically stimulated by 1 to 40 pulses. Florescence signals are recorded at 380 (calcium sensitive) and 358 (calcium insensitive) nm excitation. Ca2+ is calculated assuming non-instantaneous equilibrium with fura-2. The rate constant of calcium decay decreased significantly with increasing stimulation duration in the FDB fibers, but remained relatively constant in the soleus fibers. This is due to expected differences in parvalbumin concentration between fast-twitch and slow-twitch fibers. In fast-twitch fibers parvalbumin becomes increasing saturated by calcium with increasing stimulation durations and can no longer contribute to the decay of calcium. However, there is negligible amounts of parvalbumin in slow-twitch fibers, therefore they do not exhibit this slowing of calcium decay effect. Quantification of the SR calcium ATPase, troponin C and parvalbumin content, using SDS page and immunoblotting techniques confirmed that there was a significant difference in the concentration of parvalbumin between rat FDB (1.2 mM calcium binding site concentration) and soleus fibers ({dollar}<{dollar}50 {dollar}\mu{dollar}M calcium binding site concentration). Unexpectedly there was no significant difference in the concentration of SR calcium ATPase, and troponin C. The values determined by the gel and immunoblot Quantification were well supported by preliminary modeling analysis of the Ca2+ decay. In conclusion, there are significant differences in the decay of Ca2+ in rat fast-twitch and slow-twitch muscle, which is due to differences in parvalbumin concentration. This indicates that parvalbumin has a significant role in the decay of calcium in mammalian skeletal muscle fibers.
    Description
    University of Maryland, Baltimore. Biochemistry and Molecular Biology. Ph.D. 1996
    Keyword
    Biology, Cell
    Biology, Animal Physiology
    Chemistry, Biochemistry
    Biophysics, General
    Muscle Fibers, Fast-Twitch
    Muscle Fibers, Slow-Twitch
    Rats
    Sarcoplasmic Reticulum Calcium-Transporting ATPases
    Troponin C
    Identifier to cite or link to this item
    http://hdl.handle.net/10713/1494
    Collections
    Theses and Dissertations All Schools
    Theses and Dissertations School of Medicine

    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.