Abstract
Human colon has been suggested to play an important role in calcium absorption especially after extensive disease or resection of the small intestine. We have previously demonstrated the presence of a carrier-mediated calcium uptake mechanism in the human colonic luminal membrane vesicles. Current studies were, therefore, undertaken to investigate the mechanism(s) of calcium exit across the basolateral membrane domain of the human colon. Human colonic basolateral membrane vesicles (BLMVs) were isolated and purified from mucosal scrapings of organ donor colons, utilizing a technique developed in our laboratory. 45Ca uptake was measured by a rapid filtration technique. 45Ca uptake represented transport into the intravesicular space as evidenced by an osmolarity study and by the demonstration of Ca2+ efflux from calcium preloaded vesicles by Ca2+ ionophore A23187. Calcium uptake was stimulated by Mg2+ ATP. The kinetic parameters for ATP-dependent Ca2+ uptake revealed saturation kinetics with Michaelis constant (K m) of 0.22 ± 0.04 μM and a maximum rate of uptake (V max) of 0.38 ± 0.12 nmol/mg protein/min. The K m of ATP concentration required for half maximal Ca2+ uptake was 0.39 ± 0.04 mM. ATP-stimulated calcium uptake into these vesicles was further stimulated in the presence of calmodulin and was inhibited by calmodulin antagonist, trifluoperazine. Uptake of 45Ca into BLMVs was markedly inhibited by cis-Na+ but was significantly stimulated by trans-Na+ (40–50% stimulation). Our results demonstrate the presence of a Mg2+/ATP-dependent calmodulin-regulated Ca2+ transport system and a Na+–Ca2+ exchange process in the human colonic basolateral membranes.
Similar content being viewed by others
REFERENCES
Petith MM, Schedl HP: Intestinal adaptation to dietary calcium restriction: in vivo cecal and colonic calcium transport in the rat. Gastroenterology 71(6):1039–1042, 1976
Lee DBN, Walling MW, Gafter V, Silis V, Cobum JW: Calcium and inorganic phosphate transport in rat colon. J Clin Invest 65:1326–1331, 1980
Grinstead WC, P. CYC, K. GJ. Effect of 1,25-dihydroxyvitamin D3 on calcium absorption in the colon of healthy humans. Am J Physiol 247:G189–G192, 1984
Lointier P, Meggouh F, Dechelotte P, Pezet D, Ferrier C, Chipponi J, et al: 1,25-dihydroxyvitamin D-3 receptors and human colon adenocarcinoma. Br J Surg 78:435–439, 1991
Hylander E, Ladefoged K, Jarnum S: Calcium absorption after intestinal resection. The importance of a preserved colon. Scand J Gastroenterol 25:705–710, 1990
Hylander E, Ladefoged K, Jarnum S: The importance of the colon in calcium absorption following small-intestinal resection. Scand J Gastroenterol 15:55–60, 1980
Avioli LV: Intestinal absorption of calcium. Arch Intern Med 129(2):345–355, 1972
Walling MW, Rothman SS: Apparent increase in carrier affinity for intestinal calcium transport following dietary calcium restriction. J Biol Chem 245(19):5007–5011, 1970
Favus MJ: Factors that influence absorption and secretion of calcium in the small intestine and colon. Am J Physiol 248(2 Pt 1):G147–G157, 1985
Ghishan FK, Arab N, Nylander W: Characterization of calcium uptake by brush border membrane vesicles of human small intesine. Gastroenterology 96:122–129, 1989
Bronner F, Pansu D, Stein WD: An analysis of calcium transport across rat intestine. Am J Physiol 250:G561–G569, 1986
Hildmann B, Schmidt A, Murer H: Ca++-transport across basal-lateral plasma membranes from rat small intestinal epithelial cells. J Membr Biol 65(1-2):55–62, 1982
Ghijsen WE, Van Os CH, Heizmann CW, Murer H: Regulation of duodenal Ca2+ pump by calmodulin and vitamin Ddependent Ca2+-binding protein. Am J Physiol 251(2 Pt 1):G223–G229, 1986
Nellans HN, Popovitch JE: Calmodulin-regulated, ATP-driven calcium transport by basolateral membranes of rat small intestine. J Biol Chem 256(19):9932–9936, 1981
Tsukamoto Y, Suki WN, Liang CT, Sacktor B: Ca2+-dependent ATPases in the basolateral membrane of rat kidney cortex. J Biol Chem 261(6):2718–2724, 1986
Jayakumar A, Cheng L, Liang CT, Sacktor B: Sodium gradientdependent calcium uptake in renal basolateral membrane vesicles. Effect of parathyroid hormone. J Biol Chem 259(17):10827–10833, 1984
van Heeswijk MP, Geertsen JA, van Os CH: Kinetic properties of the ATP-dependent Ca2+ pump and the Na+/Ca2+ exchange system in basolateral membranes from rat kidney cortex. J Membr Biol 79(1):19–31, 1984
Elsharydah A, Syed R, Tyagi S, Khudeira AK, Harig JM, Dudeja PK: Calcium transport mechanism in human colonic apical membrane vesicles. Gastroenterology 109:876–884, 1995
Tyagi S, Joshi V, Alrefai WA, Gill RK, Ramaswamy K, Dudeja PK: Evidence for a Na+-H+ exchange across human colonic basolateral plasma membranes purified from organ donor colons. Dig Dis Sci 45(12):2282–2289, 2000
Bradford M: A rapid and sensitive method for the quantitation of microgram quantities of protein utilizing the principle of protein-dye binding. Anal Biochem 72:248–254, 1976
Dudeja PK, Foster ES, Brasitus TA: Na+/H+ antiporter of rat colonic basolateral membrane vesicles. Am J Physiol 257:G624–G632, 1989
Shull GE, Greeb J: Molecular cloning of two isoforms of the plasma membrane Ca2+-transporting ATPase from rat brain. Structural and functional domains exhibit similarity to Na+,K+-and other cation transport ATPase. J Biol Chem 263(18):8646–8657, 1988
Ghijsen WE, De Jong MD, Van Os CH: ATP-dependent calcium transport and its correlation with Ca2+-ATPase activity in basolateral plasma membranes of rat duodenum. Biochim Biophys Acta 689(2):327–336, 1982
Kikuchi K, Kikuchi T, Ghishan FK: Characterization of calcium transport by basolateral membrane vesicles of human small intestine. Am J Physiol 255:G482–G489, 1988
Walters JR, Weiser MM: Calcium transport by rat duodenal villus and crypt basolateral membranes. Am J Physiol 252(2 Pt 1):G170–G177, 1987
van Corven EJ, Roche C, van Os CH: Distribution of Ca2+-ATPase, ATP-dependent Ca2+-transport, calmodulin and vitamin D-dependent Ca2+-binding protein along the villus-crypt axis in rat duodenum. Biochim Biophys Acta 820(2):274–282, 1985
Niggli V, Adunyah ES, Penniston JT, Carafoli E: Purified (Ca2+-Mg2+)-ATPase of the erythrocyte membrane. Reconstitution and effect of calmodulin and phospholipids. J Biol Chem 256(1):395–401, 1981
Favus MJ, Angeid-Backman E, Breyer MD, Coe FL: Effects of trifluoperazine, ouabain, and ethacrynic acid on intestinal calcium transport. Am J Physiol 244(2):G111–G115, 1983
Favus MJ, Kathpalia SC, Coe FL, Mond AE: Effects of diet calcium and 1,25-dihydroxyvitamin D3 on colon calcium active transport. Am J Physiol 238(2):G75–G78, 1980
Stoll R, Stern H, Ruppin H, Domschke W: Effect of two potent calmodulin antagonists on calcium transport of brush border and basolateral vesicles from human duodenum. Aliment Pharmacol Ther 1(5):415–424, 1987
Ghijsen WE, van Os CH: Ca-stimulated ATPase in brush border and basolateral membranes of rat duodenum with high affinity sites for Ca ions. Nature 279(5716):802–803, 1979
Murer H, Hildmann B: Transcellular transport of calcium and inorganic phosphate in the small intestinal epithelium. Am J Physiol 240(6):G409–G416, 1981
Berne RM, Levy MN (Eds): Physiology 4th Edition, St. Louis, Mo., Mosby Press, pp. 647–674
Peng JB, Chen XZ, Berger UV, Weremowicz S, Morton CC, Vassilev PM, et al: Human calcium transport protein CaT1. Biochem Biophys Res Commun 278(2):326–332, 2000
Author information
Authors and Affiliations
Rights and permissions
About this article
Cite this article
Saksena, S., Ammar, M.S., Tyagi, S. et al. Mechanisms of Calcium Transport in Human Colonic Basolateral Membrane Vesicles. Dig Dis Sci 47, 2306–2315 (2002). https://doi.org/10.1023/A:1020151730940
Issue Date:
DOI: https://doi.org/10.1023/A:1020151730940