TY - JOUR
T1 - Extrinsic innervation modulates canine jejunal transport of glutamine, alanine, leucine, and glucose
AU - Foley, M. K.
AU - Inoue, Y.
AU - Souba, W. W.
AU - Sarr, M. G.
N1 - Funding Information:
Supported in part by USPHS NIH Grant DK39337 (M.G.S.) and the Mayo Foundation.
PY - 1998
Y1 - 1998
N2 - Background. We previously showed a decrease in ileal glutamine transport in vitro and net absorption in vivo after extrinsic denervation of the canine jejunoileum. The aim was to determine whether extrinsic innervation modulates in vivo net absorption and in vitro transport of glutamine and other nutrients in canine jejunum. Methods. In vivo net jejunal uptakes of glutamine, alanine, leucine, and glucose were measured in five dogs before and 2 and 8 weeks after a model neurally isolating in situ the jejunoileum (extrinsic denervation, intestinal transection). To assess mechanisms, carrier-mediated uptakes were quantitated in jejunal brush border membrane vesicles from six dogs before and at 2 and 8 weeks after neural isolation of the jejunoileum and compared with six control dogs with fully intact extrinsic innervation. Results. In vivo net absorption of glutamine decreased at 2 weeks (p < 0.05) and returned to normal values at 8 weeks; net absorptions of leucine, alanine, and glucose were decreased at both 2 and 8 weeks. In vitro brush border membrane vesicles transport of glutamine, leucine, and alanine followed the patterns of in vivo absorption, but glucose transport did not differ at any time point. Decreased glutamine uptake at 2 weeks resulted from a decrease in V(max) rather than a change in K in sodium- dependent carrier-mediated transport. Conclusions. Extrinsic denervation down-regulated carrier-mediated transport of amino acids but not glucose. Decreased in vitro glutamine transport was mediated in part try a decrease in number rather than affinity of sodium-dependent transporters.
AB - Background. We previously showed a decrease in ileal glutamine transport in vitro and net absorption in vivo after extrinsic denervation of the canine jejunoileum. The aim was to determine whether extrinsic innervation modulates in vivo net absorption and in vitro transport of glutamine and other nutrients in canine jejunum. Methods. In vivo net jejunal uptakes of glutamine, alanine, leucine, and glucose were measured in five dogs before and 2 and 8 weeks after a model neurally isolating in situ the jejunoileum (extrinsic denervation, intestinal transection). To assess mechanisms, carrier-mediated uptakes were quantitated in jejunal brush border membrane vesicles from six dogs before and at 2 and 8 weeks after neural isolation of the jejunoileum and compared with six control dogs with fully intact extrinsic innervation. Results. In vivo net absorption of glutamine decreased at 2 weeks (p < 0.05) and returned to normal values at 8 weeks; net absorptions of leucine, alanine, and glucose were decreased at both 2 and 8 weeks. In vitro brush border membrane vesicles transport of glutamine, leucine, and alanine followed the patterns of in vivo absorption, but glucose transport did not differ at any time point. Decreased glutamine uptake at 2 weeks resulted from a decrease in V(max) rather than a change in K in sodium- dependent carrier-mediated transport. Conclusions. Extrinsic denervation down-regulated carrier-mediated transport of amino acids but not glucose. Decreased in vitro glutamine transport was mediated in part try a decrease in number rather than affinity of sodium-dependent transporters.
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U2 - 10.1016/S0039-6060(98)70186-2
DO - 10.1016/S0039-6060(98)70186-2
M3 - Article
C2 - 9526525
AN - SCOPUS:0031887187
SN - 0039-6060
VL - 123
SP - 321
EP - 329
JO - Surgery
JF - Surgery
IS - 3
ER -