The influence of luminal pH on transport of neutral and charged dipeptides by rat small intestine, in vitro

被引:11
作者
Lister, N
Bailey, PD
Collier, ID
Boyd, CAR
Bronk, JR
机构
[1] UNIV YORK, DEPT BIOL, YORK YO1 5DD, N YORKSHIRE, ENGLAND
[2] HERIOT WATT UNIV, DEPT CHEM, EDINBURGH EH14 4AS, MIDLOTHIAN, SCOTLAND
[3] UNIV OXFORD, DEPT HUMAN ANAT, OXFORD OX1 3QX, ENGLAND
来源
BIOCHIMICA ET BIOPHYSICA ACTA-BIOMEMBRANES | 1997年 / 1324卷 / 02期
基金
英国惠康基金;
关键词
dipeptide; transport; pH; intestine; rat;
D O I
10.1016/S0005-2736(96)00230-1
中图分类号
Q5 [生物化学]; Q7 [分子生物学];
学科分类号
071010 ; 081704 ;
摘要
Four hydrolysis-resistant dipeptides (D-phenylalanyl-L-alanine, D-phenylalanyl-L-glutamine, D-phenylalanyl-L-glutamate and D-phenylalanyl-L-lysine) were synthesized to investigate the effects of net charge on transmural dipeptide transport by isolated jejunal loops of rat small intestine. At a luminal pH of 7.4 and a concentration of 1 mM the two dipeptides with a net charge of -1 and +1 were transported at substantially slower rates (18 +/- 1.3 and 8.4 +/- 1.3 nmol min(-1) (g dry wt.)(-1), respectively) than neutral D-phenylalanyl-L-alanine and D-phenylalanyl-L-glutamine (87 +/- 0.2 and 197 +/- 14 nmol min(-1) (g dry wt.)(-1), respectively). We investigated the effects of luminal pH on dipeptide transport by varying the NaHCO3 content of Krebs Ringer perfusate equilibrated with 95%0(2)/5% CO2. The pH changes did not affect water transport, but serosal glucose appearance increased significantly at pH 6.8. Transmural transport of D-phenylalanyl-L-alanine and D-phenylalanyl-L-glutamine at pH 6.8 was stimulated (P < 0.01) by 61% and 49%, respectively, whereas the lower pH increased the rate for negatively charged D-phenylalanyl-L-glutamate by 306% (P < 0.01) and decreased that for positively charged D-phenylalanyl-L-lysine by 46% (P < 0.05). Increasing luminal pH to 8.0 inhibited D-phenylalanyl-L-alanine transport by 60%, whereas D-phenylalanyl-L-lysine transport was 60% faster.
引用
收藏
页码:245 / 250
页数:6
相关论文
共 16 条
[1]   PH-INDUCED COLD LABILITY OF RABBIT SKELETAL-MUSCLE PHOSPHOFRUCTOKINASE [J].
BOCK, PE ;
FRIEDEN, C .
BIOCHEMISTRY, 1974, 13 (20) :4191-4196
[2]  
BRONK JR, 1995, J PHYSIOL-LONDON, V489P, pP105
[3]  
BRONK JR, 1995, ITAL J GASTROENTEROL, V27, P150
[4]  
DANIEL H, 1992, J BIOL CHEM, V267, P9565
[5]   EXPRESSION CLONING OF A MAMMALIAN PROTON-COUPLED OLIGOPEPTIDE TRANSPORTER [J].
FEI, YJ ;
KANAI, Y ;
NUSSBERGER, S ;
GANAPATHY, V ;
LEIBACH, FH ;
ROMERO, MF ;
SINGH, SK ;
BORON, WF ;
HEDIGER, MA .
NATURE, 1994, 368 (6471) :563-566
[6]   IS INTESTINAL PEPTIDE-TRANSPORT ENERGIZED BY A PROTON GRADIENT [J].
GANAPATHY, V ;
LEIBACH, FH .
AMERICAN JOURNAL OF PHYSIOLOGY, 1985, 249 (02) :G153-G160
[7]   THE ACUTE REGULATION OF GLUCOSE-ABSORPTION, TRANSPORT AND METABOLISM IN RAT SMALL-INTESTINE BY INSULIN INVIVO [J].
KELLETT, GL ;
JAMAL, A ;
ROBERTSON, JP ;
WOLLEN, N .
BIOCHEMICAL JOURNAL, 1984, 219 (03) :1027-1035
[8]   DIPEPTIDE TRANSPORT AND HYDROLYSIS IN ISOLATED LOOPS OF RAT SMALL-INTESTINE - EFFECTS OF STEREOSPECIFICITY [J].
LISTER, N ;
SYKES, AP ;
BAILEY, PD ;
BOYD, CAR ;
BRONK, JR .
JOURNAL OF PHYSIOLOGY-LONDON, 1995, 484 (01) :173-182
[9]   MOLECULAR-CLONING OF PEPT-2, A NEW MEMBER OF THE H+/PEPTIDE COTRANSPORTER FAMILY, FROM HUMAN KIDNEY [J].
LIU, W ;
LIANG, R ;
RAMAMOORTHY, S ;
FEI, YJ ;
GANAPATHY, ME ;
HEDIGER, MA ;
GANAPATHY, V ;
LEIBACH, FH .
BIOCHIMICA ET BIOPHYSICA ACTA-BIOMEMBRANES, 1995, 1235 (02) :461-466
[10]  
MEREDITH D, 1995, J MEMBRANE BIOL, V145, P1