HOME HELP FEEDBACK SUBSCRIPTIONS ARCHIVE SEARCH TABLE OF CONTENTS		QUICK SEARCH:   [advanced] Author: Keyword(s): Year:  Vol:  Page:

This Article Full Text Full Text (PDF) Alert me when this article is cited Alert me if a correction is posted Citation Map Services Email this article to a friend Similar articles in this journal Similar articles in PubMed Alert me to new issues of the journal Download to citation manager Request Permissions Citing Articles Citing Articles via HighWire Citing Articles via Google Scholar Google Scholar Articles by Xu, G. Articles by Salen, G. Search for Related Content PubMed PubMed Citation Articles by Xu, G. Articles by Salen, G. Social Bookmarking                      What's this?

Journal of Lipid Research, Vol. 41, 298-304, February 2000
Copyright © 2000 by Lipid Research, Inc.

Original Article

Ileal bile acid transport regulates bile acid pool, synthesis, and plasma cholesterol levels differently in cholesterol-fed rats and rabbits

Correspondence to: Gerald Salen

We investigated the effect of ileal bile acid transport on the regulation of classic and alternative bile acid synthesis in cholesterol-fed rats and rabbits. Bile acid pool sizes, fecal bile acid outputs (synthesis rates), and the activities of cholesterol 7-hydroxylase (classic bile acid synthesis) and cholesterol 27-hydroxylase (alternative bile acid synthesis) were related to ileal bile acid transporter expression (ileal apical sodium-dependent bile acid transporter, ASBT). Plasma cholesterol levels rose 2.1-times in rats (98 ± 19 mg/dl) and 31-times (986 ± 188 mg/dl) in rabbits. The bile acid pool size remained constant (55 ± 17 mg vs. 61 ± 18 mg) in rats but doubled (254 ± 46 to 533 ± 53 mg) in rabbits. ASBT protein expression did not change in rats but rose 31% (P < 0.05) in rabbits. Fecal bile acid outputs that reflected bile acid synthesis increased 2- and 2.4-times (P < 0.05) in cholesterol-fed rats and rabbits, respectively. Cholesterol 7-hydroxylase activity rose 33% (24 ± 2.4 vs. 18 ± 1.6 pmol/mg/min, P < 0.01) and mRNA levels increased 50% (P < 0.01) in rats but decreased 68% and 79%, respectively, in cholesterol-fed rabbits. Cholesterol 27-hydroxylase activity remained unchanged in rats but rose 62% (P < 0.05) in rabbits. Classic bile acid synthesis (cholesterol 7-hydroxylase) was inhibited in rabbits because an enlarged bile acid pool developed from enhanced ileal bile acid transport. In contrast, in rats, cholesterol 7-hydroxylase was stimulated but the bile acid pool did not enlarge because ASBT did not change.

Therefore, although bile acid synthesis was increased via different pathways in rats and rabbits, enhanced ileal bile acid transport was critical for enlarging the bile acid pool size that exerted feedback regulation on cholesterol 7-hydroxylase in rabbits.—Xu, G., B. L. Shneider, S. Shefer, L. B. Nguyen, A. K. Batta, G. S. Tint, M. Arrese, S. Thevananther, L. Ma, S. Stengelin, W. Kramer, D. Greenblatt, M. Pcolinsky, and G. Salen. Ileal bile acid transport regulates bile acid pool, synthesis, and plasma cholesterol levels differently in cholesterol-fed rats and rabbits. J. Lipid Res. 2000. 41: 298–304.

Supplementary key words: bile acids, absorption, biosynthesis, cholesterol 7-hydroxylase, cholesterol 27-hydroxylase

CiteULike    Complore    Connotea    Del.icio.us    Digg    Reddit    Technorati    What's this?

This article has been cited by other articles:

				M. Miyata, Y. Matsuda, M. Nomoto, Y. Takamatsu, N. Sato, M. Hamatsu, P. A. Dawson, F. J. Gonzalez, and Y. Yamazoe Cholesterol Feeding Prevents Hepatic Accumulation of Bile Acids in Cholic Acid-Fed Farnesoid X Receptor (FXR)-Null Mice: FXR-Independent Suppression of Intestinal Bile Acid Absorption Drug Metab. Dispos., February 1, 2009; 37(2): 338 - 344. [Abstract] [Full Text] [PDF]

				C Thomas, J-F Landrier, D Gaillard, J Grober, M-C Monnot, A Athias, and P Besnard Cholesterol dependent downregulation of mouse and human apical sodium dependent bile acid transporter (ASBT) gene expression: molecular mechanism and physiological consequences Gut, September 1, 2006; 55(9): 1321 - 1331. [Abstract] [Full Text] [PDF]

				X. Chen, F. Chen, S. Liu, H. Glaeser, P. A. Dawson, A. F. Hofmann, R. B. Kim, B. L. Shneider, and K. S. Pang Transactivation of Rat Apical Sodium-Dependent Bile Acid Transporter and Increased Bile Acid Transport by 1{alpha},25-Dihydroxyvitamin D3 via the Vitamin D Receptor Mol. Pharmacol., June 1, 2006; 69(6): 1913 - 1923. [Abstract] [Full Text] [PDF]

				P Hruz, C Zimmermann, H Gutmann, L Degen, U Beuers, L Terracciano, J Drewe, and C Beglinger Adaptive regulation of the ileal apical sodium dependent bile acid transporter (ASBT) in patients with obstructive cholestasis Gut, March 1, 2006; 55(3): 395 - 402. [Abstract] [Full Text] [PDF]

				W. A. Alrefai, Z. Sarwar, S. Tyagi, S. Saksena, P. K. Dudeja, and R. K. Gill Cholesterol modulates human intestinal sodium-dependent bile acid transporter Am J Physiol Gastrointest Liver Physiol, May 1, 2005; 288(5): G978 - G985. [Abstract] [Full Text] [PDF]

				G. Xu, L.-x. Pan, H. Li, Q. Shang, A. Honda, S. Shefer, J. Bollineni, Y. Matsuzaki, G. S. Tint, and G. Salen Dietary cholesterol stimulates CYP7A1 in rats because farnesoid X receptor is not activated Am J Physiol Gastrointest Liver Physiol, May 1, 2004; 286(5): G730 - G735. [Abstract] [Full Text] [PDF]

				M. Tiemann, Z. Han, R. Soccio, J. Bollineni, S. Shefer, E. Sehayek, and J. L. Breslow Cholesterol feeding of mice expressing cholesterol 7{alpha}-hydroxylase increases bile acid pool size despite decreased enzyme activity PNAS, February 17, 2004; 101(7): 1846 - 1851. [Abstract] [Full Text] [PDF]

				D Jung, A C Fantin, U Scheurer, M Fried, and G A Kullak-Ublick Human ileal bile acid transporter gene ASBT (SLC10A2) is transactivated by the glucocorticoid receptor Gut, January 1, 2004; 53(1): 78 - 84. [Abstract] [Full Text] [PDF]

				F. Chen, L. Ma, P. A. Dawson, C. J. Sinal, E. Sehayek, F. J. Gonzalez, J. Breslow, M. Ananthanarayanan, and B. L. Shneider Liver Receptor Homologue-1 Mediates Species- and Cell Line-specific Bile Acid-dependent Negative Feedback Regulation of the Apical Sodium-dependent Bile Acid Transporter J. Biol. Chem., May 23, 2003; 278(22): 19909 - 19916. [Abstract] [Full Text] [PDF]

				C. V. Hulzebos, H. Wolters, T. Plosch, W. Kramer, S. Stengelin, F. Stellaard, P. J. J. Sauer, H. J. Verkade, and F. Kuipers Cyclosporin A and Enterohepatic Circulation of Bile Salts in Rats: Decreased Cholate Synthesis but Increased Intestinal Reabsorption J. Pharmacol. Exp. Ther., January 1, 2003; 304(1): 356 - 363. [Abstract] [Full Text] [PDF]

				D. Jung, M. Fried, and G. A. Kullak-Ublick Human Apical Sodium-dependent Bile Salt Transporter Gene (SLC10A2) Is Regulated by the Peroxisome Proliferator-activated Receptor alpha J. Biol. Chem., August 16, 2002; 277(34): 30559 - 30566. [Abstract] [Full Text] [PDF]

				G. Xu, L.-x. Pan, S. K. Erickson, B. M. Forman, B. L. Shneider, M. Ananthanarayanan, X. Li, S. Shefer, N. Balasubramanian, L. Ma, et al. Removal of the bile acid pool upregulates cholesterol 7{alpha}-hydroxylase by deactivating FXR in rabbits J. Lipid Res., January 1, 2002; 43(1): 45 - 50. [Abstract] [Full Text] [PDF]

				G. Xu, G. Salen, B. L. Shneider, M. Ananthanarayanan, S. Shefer, L. Ma, A. Batta, L. B. Nguyen, J. J. Lingutla, G. S. Tint, et al. Cholecystectomy prevents expansion of the bile acid pool and inhibition of cholesterol 7{alpha}-hydroxylase in rabbits fed cholesterol J. Lipid Res., September 1, 2001; 42(9): 1438 - 1443. [Abstract] [Full Text] [PDF]