Influx of glycyl-proline and free amino acids across intestinal brush border of phenobarbital-treated rats.
In a previous study the authors have shown that treatment with phenobarbital in the rat is followed by a generalized increase of amino acid concentration in the plasma. In order to better clarify this phenomenon, the effect of phenobarbital on intestinal protein absorption was now studied by measuring the influxes of Glycyl-L-Proline, L-Phenylalanine, L-Lysine and L-Glutamic acid across the brush border of jejunum and ileum in rats treated with phenobarbital for two or four days. No significant changes of these influxes were observed in the treated animals as compared to the controls, hence suggesting that the effect of phenobarbital on plasma levels of free amino acids is not mediated by an effect on intestinal absorption. The rate of Glycyl-Proline influx as compared to those of amino acid influxes suggests the occurrence of a carrier-mediated transport process for this dipeptide in the rat intestine as previously shown in the rabbit.
D000596:Amino Acids / Q000378:metabolism*; D000818:Animals; D003577:Cytochrome P-450 Enzyme System / Q000378:metabolism; D004151:Dipeptides / Q000378:metabolism*; D066298:In Vitro Techniques; D007408:Intestinal Absorption / Q000187:drug effects*; D007413:Intestinal Mucosa / Q000187:drug effects / Q000378:metabolism; D008297:Male; D008871:Microvilli / Q000187:drug effects / Q000378:metabolism; D010634:Phenobarbital / Q000494:pharmacology*; D011392:Proline / Q000031:analogs & derivatives / Q000378:metabolism; D051381:Rats
D000596:Amino Acids; D004151:Dipeptides; D003577:Cytochrome P-450 Enzyme System; D011392:Proline; D010634:Phenobarbital