• Login
    View Item 
    •   Home
    • UA Graduate and Undergraduate Research
    • UA Theses and Dissertations
    • Dissertations
    • View Item
    •   Home
    • UA Graduate and Undergraduate Research
    • UA Theses and Dissertations
    • Dissertations
    • View Item
    JavaScript is disabled for your browser. Some features of this site may not work without it.

    Browse

    All of UA Campus RepositoryCommunitiesTitleAuthorsIssue DateSubmit DateSubjectsPublisherJournalThis CollectionTitleAuthorsIssue DateSubmit DateSubjectsPublisherJournal

    My Account

    LoginRegister

    About

    AboutUA Faculty PublicationsUA DissertationsUA Master's ThesesUA Honors ThesesUA PressUA YearbooksUA CatalogsUA Libraries

    Statistics

    Most Popular ItemsStatistics by CountryMost Popular Authors

    Dietary and hormonal regulation of pancreatic digestive enzymes.

    • CSV
    • RefMan
    • EndNote
    • BibTex
    • RefWorks
    Thumbnail
    Name:
    azu_td_9117459_sip1_m.pdf
    Size:
    4.317Mb
    Format:
    PDF
    Description:
    azu_td_9117459_sip1_m.pdf
    Download
    Author
    Hirschi, Karen Kemper.
    Issue Date
    1990
    Keywords
    Dissertations, Academic
    Biochemistry
    Digestive enzymes.
    Advisor
    Brannon, Patsy M.
    
    Metadata
    Show full item record
    Publisher
    The University of Arizona.
    Rights
    Copyright © is held by the author. Digital access to this material is made possible by the University Libraries, University of Arizona. Further transmission, reproduction or presentation (such as public display or performance) of protected items is prohibited except with permission of the author.
    Abstract
    The activity, synthetic rate and mRNA levels of pancreatic digestive enzymes adapt to changes in their respective dietary substrates. Previous studies in vivo implicate ketones and secretin in lipase adaptation and cholecystokinin (caerulein) in protease and, possibly, amylase adaptation. These studies were undertaken to determine the direct role(s) in vitro of these nutrient and hormonal factors on digestive enzymes in cultured rat pancreatic acinar cells. Ketones, intermediates of triglyceride metabolism, did not affect lipase activity in cells isolated from rats fed commercial non-purified diet, whether cultured in media containing high or low concentrations of glucose, a competitive energy substrate. Beta(OH)-butyrate also had no affect on lipase activity in cells from high-fat fed rats in which lipase was already elevated, but did increase lipase activity dose-dependently in cells isolated from rats fed a purified low-fat diet. Importantly, lipase levels were higher in cells from rats fed high fat diet, compared to those of low-fat fed rats, demonstrating that dietary adaptation persisted in culture. The role of ketones in lipase regulation appeared to be more complex than originally proposed, and they may not be the sole mediator. Direct effects of secretin and caerulein on the activity, secretion and relative synthesis of lipase were studied. Secretin significantly increased media lipase activity biphasically after 12 h, but had no effect on cellular lipase activity. After 24 h, secretin had no effect on lipase activity or relative synthesis of pancreatic enzymes (amylase, lipase, chymotrypsin, trypsin, elastase). In cultured cells, enzyme activities decreased over time, while media activities increased. Amylase relative synthesis decreased over time, while that of the proteases increased. Caerulein further decreased cellular content of all enzymes and increased media amylase and lipase activities. Caerulein, however, increased the relative synthesis of trypsin (p < 0.05) and chymotrypsin (p < 0.06), supporting its proposed role in protease, but not amylase, adaptation. These studies did not, however, support definitive roles of ketones or secretin in lipase regulation; perhaps they have interactive effects, or act in conjunction with other potential regulators, in the dietary adaptation of lipase.
    Type
    text
    Dissertation-Reproduction (electronic)
    Degree Name
    Ph.D.
    Degree Level
    doctoral
    Degree Program
    Nutritional Sciences
    Graduate College
    Degree Grantor
    University of Arizona
    Collections
    Dissertations

    entitlement

     
    The University of Arizona Libraries | 1510 E. University Blvd. | Tucson, AZ 85721-0055
    Tel 520-621-6442 | repository@u.library.arizona.edu
    DSpace software copyright © 2002-2017  DuraSpace
    Quick Guide | Contact Us | Send Feedback
    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.