In birds , NHE 2 is major brush - border Na 1 / H 1 exchanger in colon and is increased by a low - NaCl diet
نویسنده
چکیده
M. DONOWITZ,1 C. DE LA HORRA,2 M. L. CALONGE,2 I. S. WOOD,2 J. DYER,2 S. M. GRIBBLE,2 F. SANCHEZ DE MEDINA,1 C. M. TSE,1 S. P. SHIRAZI-BEECHEY,3 AND A. A. ILUNDAIN2 1Departments of Medicine and Physiology, GI Division, Johns Hopkins University School of Medicine, Baltimore, Maryland 21205-2195; 2Departments of Animal Physiology and Biology, School of Pharmacy, University of Seville, E-41009 Seville, Spain; and 3Institute of Biological Sciences, University of Wales, Aberystwyth, S423 3DD United Kingdom
منابع مشابه
In birds, NHE2 is major brush-border Na+/H+exchanger in colon and is increased by a low-NaCl diet.
We previously reported that mammalian small intestinal and colonic brush borders (BBs) contained both epithelial Na+/H+exchangers NHE2 and NHE3. We now show that, in the avian (chicken) colon, NHE2 is the major functional isoform under basal conditions and when stimulated by a low-NaCl diet. Hubbard chickens were maintained for 2 wk on a high- or low-NaCl diet. After the chickens were killed, t...
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We investigated whether highly purified preparations of basal (fetal-facing) membrane isolated from normal term human placentas possess Na(+)-H+ exchanger activity. Uptake of Na+ into basal membrane vesicles was stimulated many-fold by an outwardly directed H+ gradient. This H(+)-gradient-dependent uptake was inhibitable by amiloride and its analogues. Na+ uptake in these vesicles did not occur...
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The effects of aldosterone and arginine vasotocin (AVT) on intestinal Na(+)/H(+) exchange (NHE) and Na(+)-sugar cotransport (SGLT-1) activities have been investigated using brush-border membrane vesicles isolated from Hubbard chicken small and large intestines, and they were compared with those induced by either Na(+) depletion or dehydration. Na(+) depletion was induced by feeding the chickens...
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