Scholarly Communications Project

Lysine and Glycyl-L-Sarcosine Absorption Across Ovine Forestomach Epithelium In Vitro

by

Martha Quinn McCollum

Thesis submitted to the Faculty of the Virginia Tech in partial fulfillment of the requirements for the degree of

M.S.

in

Animal and Poultry Sciences

Approved

K. E. Webb, Jr., Chair
J. H. Herbein, Jr.
E. T. Kornegay

August 20, 1996
Blacksburg, Virginia

Abstract

Lysine absorption by ruminal and omasal epithelia was studied using parabiotic chambers that were sampled for 60-min. Lysine appearance in serosal buffers and the accumulation of lysine in tissues increased linearly (P < .001) with time. Lysine appearance in serosal buffers of ruminal tissue increased proportionally as the concentration of lysine increased in mucosal buffers. However, lysine appearance in serosal buffers of omasal tissue increased proportionally to a substrate concentration of 1.5 mM, then plateaued. Total absorption (tissue accumulation plus serosal appearance) increased linearly for ruminal tissue; however, for omasal tissue, total absorption increased linearly to 1.5 mM (P < .001), then plateaued. Using omasal epithelium, glycyl-L-sarcosine (Gly-Sar; .1 mM) absorption was studied during co-incubation with glycine and peptide substrates (each at 5 mM). Accumulation of Gly-Sar in omasal epithelium was greatest (P < .05) when Gly-Sar was present alone. Glycine inhibited (P < .05) Gly-Sar accumulation by 20%, whereas peptide substrates inhibited (P < .05) Gly-Sar accumulation by 60 to 85%. The absorption of Gly-Sar (.1 mM) alone or during co-incubation with either 10 mM butyric acid, or a mixture of VFA was also studied. Accumulation of Gly-Sar in tissue was greatest (P < .05) when Gly-Sar was present alone; butyric acid and VFA inhibited (P < .05) Gly-Sar accumulation by 50 to 84%. These results suggest absorption of amino acids and peptides by the omasum, and also suggest the mechanism involves mediated as well as possibly paracellular transport.

Full text (PDF) 414,848 Bytes

The author grants to Virginia Tech or its agents the right to archive and display their thesis or dissertation in whole or in part in the University Libraries in all forms of media, now or hereafter known. The author retains all proprietary rights, such as patent rights. The author also retains the right to use in future works (such as articles or books) all or part of this thesis or dissertation.
[ETD main page] [Search ETDs][etd.vt.edu] [SCP home page] [library home page]

Send Suggestions or Comments to webmaster@scholar.lib.vt.edu