The regionalization of PepT1, NBAT and EAAC1 transporters in the small intestine of rats are unchanged from birth to adulthood.
The ontogenetic development of PepT1, NBAT and EAAC1 along the vertical and horizontal axes of the rat small intestine was evaluated using semiquantitative reverse transcriptase-polymerase chain reaction (RT-PCR) and immunohistochemistry. The proximodistal profiles of mRNA levels showed that PepT1 was evenly distributed, whereas NBAT had greater expression in the proximal part, and EAAC1 in the distal part. These regionalizations were the same from postnatal days 4 to 50. PepT1 and NBAT proteins were detected in the microvilli of enterocytes along the length of the villi. NBAT was also found in the cytoplasm. Surprisingly, EAAC1 was located exclusively in the microvilli of enterocytes in the crypt and the bases of the villi. These protein expression patterns were similar in all parts of the small intestine (proximal, median and distal), at all ages. We conclude that the expression of PepT1, NBAT or EAAC1 are differently regulated according to both the horizontal and vertical axes.
Rome
Sophie
S
UMR 914, Physiologie de la Nutrition et du Comportement Alimentaire, Institut National Agronomique Paris-Grignon, Paris, France.
Barbot
Laurence
L
Windsor
Eugénie
E
Kapel
Nathalie
N
Tricottet
Viviane
V
Huneau
Jean-François
JF
Reynes
Michel
M
Gobert
Jean-Gérard
JG
Tomé
Daniel
D
D000375:Aging / Q000378:metabolism*; D027322:Amino Acid Transport System X-AG; D026923:Amino Acid Transport Systems, Basic / Q000235:genetics / Q000378:metabolism*; D026921:Amino Acid Transport Systems, Neutral / Q000235:genetics / Q000378:metabolism*; D000818:Animals; D000831:Animals, Newborn; D002352:Carrier Proteins / Q000235:genetics / Q000378:metabolism*; D020895:Enterocytes / Q000378:metabolism; D050580:Excitatory Amino Acid Transporter 3; D005260:Female; D018507:Gene Expression Regulation, Developmental / Q000502:physiology; D050491:Glutamate Plasma Membrane Transport Proteins; D007150:Immunohistochemistry; D007408:Intestinal Absorption / Q000502:physiology; D007421:Intestine, Small / Q000254:growth & development* / Q000378:metabolism; D008297:Male; D008871:Microvilli / Q000378:metabolism; D000074011:Peptide Transporter 1; D012333:RNA, Messenger / Q000032:analysis; D051381:Rats; D017207:Rats, Sprague-Dawley; D020133:Reverse Transcriptase Polymerase Chain Reaction; D027981:Symporters; D014018:Tissue Distribution
D027322:Amino Acid Transport System X-AG; D026923:Amino Acid Transport Systems, Basic; D026921:Amino Acid Transport Systems, Neutral; D002352:Carrier Proteins; D050580:Excitatory Amino Acid Transporter 3; D050491:Glutamate Plasma Membrane Transport Proteins; D000074011:Peptide Transporter 1; D012333:RNA, Messenger; C489940:Slc15a1 protein, rat; C493398:Slc1a1 protein, rat; C081009:Slc3a1 protein, rat; D027981:Symporters