PMID- 10564700
OWN - NLM
STAT- MEDLINE
DCOM- 20000127
LR  - 20131121
IS  - 0958-0670 (Print)
IS  - 0958-0670 (Linking)
VI  - 84
IP  - 6
DP  - 1999 Nov
TI  - A monocarboxylate transporter MCT1 is located at the basolateral pole of rat
      jejunum.
PG  - 1033-42
AB  - We have functionally expressed and identified a monocarboxylate transporter
      (MCT1) from rat jejunal enterocyte and we provide evidence for its basolateral
      localization. Poly(A)+ RNA isolated from rat jejunum was injected into Xenopus
      laevis oocytes and expression of a proton-lactate symporter was investigated by
      means of L-[14C]lactate uptake. The existence of an endogenous capacity for
      L-lactate transport was demonstrated; when, however, oocytes were injected with
      jejunal mRNA, an expressed L-lactate uptake was seen which differed from the
      endogenous transporter since it was significantly pH dependent. After sucrose
      density gradient fractionation, the highest expression of the pH-dependent
      lactate uptake was detected with the mRNA size fraction of about 2-3 kb in
      length. The substrate specificity, stereoselectivity and sensitivity to pCMBS (an
      organomercurial thiol reagent that modifies cysteine residues) of the expressed
      transport were in good agreement with results previously obtained using isolated 
      jejunal basolateral membranes. Using the reverse transcriptase-polymerase chain
      reaction, the presence of mRNA coding for the MCT1 isoform was demonstrated in
      jejunal enterocytes. These data, together with previous results, suggest that
      MCT1 is a major route for lactate efflux across the basolateral membrane of rat
      jejunum; this is in contrast to current opinion which restricts the presence of
      MCT1 to the apical membrane of the whole small intestine.
FAU - Orsenigo, M N
AU  - Orsenigo MN
AD  - Dipartimento di Fisiologia e Biochimica Generali, Universita di Milano, via
      Celoria 26, I-20133 Milano, Italy. novella.orsenigo@unimi.it
FAU - Tosco, M
AU  - Tosco M
FAU - Bazzini, C
AU  - Bazzini C
FAU - Laforenza, U
AU  - Laforenza U
FAU - Faelli, A
AU  - Faelli A
LA  - eng
SI  - GENBANK/AJ236865
PT  - Journal Article
PL  - England
TA  - Exp Physiol
JT  - Experimental physiology
JID - 9002940
RN  - 0 (Carrier Proteins)
RN  - 0 (Monocarboxylic Acid Transporters)
RN  - 0 (RNA, Messenger)
RN  - 33X04XA5AT (Lactic Acid)
RN  - 59-85-8 (p-Chloromercuribenzoic Acid)
SB  - IM
MH  - Amino Acid Sequence
MH  - Animals
MH  - Base Sequence
MH  - Carrier Proteins/biosynthesis/genetics/*metabolism
MH  - Hydrogen-Ion Concentration
MH  - Jejunum/*metabolism
MH  - Lactic Acid/metabolism
MH  - Male
MH  - Microinjections
MH  - Molecular Sequence Data
MH  - Monocarboxylic Acid Transporters
MH  - Oocytes/metabolism
MH  - RNA, Messenger/metabolism
MH  - Rats
MH  - Rats, Wistar
MH  - Reverse Transcriptase Polymerase Chain Reaction
MH  - Xenopus laevis
MH  - p-Chloromercuribenzoic Acid/pharmacology
EDAT- 1999/11/24 00:00
MHDA- 1999/11/24 00:01
CRDT- 1999/11/24 00:00
PHST- 1999/11/24 00:00 [pubmed]
PHST- 1999/11/24 00:01 [medline]
PHST- 1999/11/24 00:00 [entrez]
AID - PHY_1918 [pii]
PST - ppublish
SO  - Exp Physiol. 1999 Nov;84(6):1033-42.