title: Amino acid transport by the helicoidal colon of the new-born pig.
abstract: The proximal colon of the new-born pig maintains a stable short-circuit current which is partly dependent upon the presence of methionine. This interaction betweeen methionine and short-circuit current shows Michaelis-Menten knetics with a Km of 0.24 mM and a V of 27 muA.cm-2. The net flux of methionine to the serosal surface of proximal colons also shows a hyperbolic relation to the external concentration of methionine (Km 0.38 mM; V 10.4 nmol.cm-2. min-1). The proximal colon concentrates methionine within its epithelium giving a mucosal to medium ratio of 11.2 +/- 1.9 (90 min incubation in 1 mM methionine). The ability of the colon to transport methionine across and concentrate methionine within its mucosa is maintained for at least 24 h after birth. Colonic transport of amino acids could be physiologically important in the pig, where the immediate post-natal transfer of immune globulins has been shown to cause a temporary inhibition of normal intestinal function.
mesh_terms: D000818:Animals; D000831:Animals, Newborn; D001693:Biological Transport, Active; D003106:Colon / Q000378:metabolism* / Q000502:physiology; D004553:Electric Conductivity; D007413:Intestinal Mucosa / Q000378:metabolism* / Q000502:physiology; D007700:Kinetics; D008564:Membrane Potentials; D008715:Methionine / Q000378:metabolism*; D013552:Swine
chemical_list: D008715:Methionine