TY - JOUR
T1 - Beta-amino acid transport in pig small intestine in vitro by a high-affinity, chloride-dependent carrier
AU - Munck, Lars Kristian
AU - Grøndahl, Marie Louise
AU - Skadhauge, Erik
PY - 1995/8/23
Y1 - 1995/8/23
N2 - This study describes unidirectional influx of amino acids and d-glucose across the small intestinal brush-border membrane of fully weaned eight week old pigs. Influx is minimal in the duodenum and maximal in the distal and/or mid small intestine. Influx of β-alanine, taurine and N-ethyl-aminoisobutyric acid is chloride-dependent. The activation stoichiometry for taurine influx is 1.0 ± 0.2 chloride/2.4 ± 0.3 sodium/ 1 taurine. Influx of D-glucose, lysine, glycine and glutamate is chloride-independent. An ABC test demonstrates a common β-amino acid carrier: (a) the apparent affinity constant K 1 2Taurine is 44 ± 13 μM (means ± S.D.) and the inhibitory constant (KiTaurine) against β-alanine influx is 41 ± 5 μM (means ± S.E.). (b) K 1 2β-alanine is 97 ± 23 μM and Kiβ-alanine against taurine influx is 160 ± 22 μM. (c) KiHypotaunne against taurine and β-alanine influx is 43 ± 4 (n = 7) and 22 ± 5 μM (n = 7), respectively. In conclusion, a high affinity, low capacity, sodium- and chloride-dependent carrier of β-amino acids is present in pig small intestine.
AB - This study describes unidirectional influx of amino acids and d-glucose across the small intestinal brush-border membrane of fully weaned eight week old pigs. Influx is minimal in the duodenum and maximal in the distal and/or mid small intestine. Influx of β-alanine, taurine and N-ethyl-aminoisobutyric acid is chloride-dependent. The activation stoichiometry for taurine influx is 1.0 ± 0.2 chloride/2.4 ± 0.3 sodium/ 1 taurine. Influx of D-glucose, lysine, glycine and glutamate is chloride-independent. An ABC test demonstrates a common β-amino acid carrier: (a) the apparent affinity constant K 1 2Taurine is 44 ± 13 μM (means ± S.D.) and the inhibitory constant (KiTaurine) against β-alanine influx is 41 ± 5 μM (means ± S.E.). (b) K 1 2β-alanine is 97 ± 23 μM and Kiβ-alanine against taurine influx is 160 ± 22 μM. (c) KiHypotaunne against taurine and β-alanine influx is 43 ± 4 (n = 7) and 22 ± 5 μM (n = 7), respectively. In conclusion, a high affinity, low capacity, sodium- and chloride-dependent carrier of β-amino acids is present in pig small intestine.
KW - Amino acid
KW - Biological transport
KW - Chloride
KW - Glucose
KW - Physiology
KW - Small intestine
KW - Swine
UR - http://www.scopus.com/inward/record.url?scp=0029133796&partnerID=8YFLogxK
U2 - 10.1016/0005-2736(95)00107-E
DO - 10.1016/0005-2736(95)00107-E
M3 - Article
C2 - 7654750
AN - SCOPUS:0029133796
VL - 1238
SP - 49
EP - 56
JO - Biochimica et Biophysica Acta - Biomembranes
JF - Biochimica et Biophysica Acta - Biomembranes
SN - 0005-2736
IS - 1
ER -