Lysine and Glycyl-l-sarcosine Absorption across Ovine Forestomach Epithelium in Vitro
نویسندگان
چکیده
To define the interactions between the absorption of glycyl-L-sarcosine (Gly-Sar; .1mM) and glycine, L-methionylglycine, glycyl-L-leucine, L-carnosine, or Lmethionylglycyl-L-methionyl-L-methionine (each at 5 mM), ovine omasal epithelium was collected from eight wethers (avg. BW = 69 kg) and mounted in parabiotic chambers. [1,2]-[C]Glycyl-L-sarcosine was used as a marker to monitor the presence of Gly-Sar. Accumulation of Gly-Sar in the omasal epithelium was greatest (P < .05) when only GlySar was present. Glycine inhibited (P < .05) Gly-Sar accumulation by 20%, while peptide substrates inhibited (P < .05) Gly-Sar accumulation by 60 to 85%. The appearance of Gly-Sar in serosal buffers increased linearly (P < .001) during the 60-min incubation. There was a tendency for Gly-Sar appearance in serosal buffers to be stimulated by the presence of other substrates . In a second experiment, ovine omasal epithelium was collected from four lambs (avg. BW = 47 kg) to determine the interactions between the absorption of Gly-Sar (.1mM) alone or co-incubated with either 10 mM butyric acid, or a mixture of VFA (50 mM acetic acid, 40 mM propionic acid, and 10 mM butyric acid). Accumulation of Gly-Sar in the omasal epithelia was greatest (P < .05) when only Gly-Sar was present; butyric acid inhibited (P < .05) Gly-Sar accumulation by
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