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 Copyright Permission Citing Articles Citing Articles via HighWire Citing Articles via Google Scholar Google Scholar Articles by Ney, D. M. Articles by Adamo, M. L. Search for Related Content PubMed PubMed Citation Articles by Ney, D. M. Articles by Adamo, M. L. Pubmed/NCBI databases Compound via MeSH Substance via MeSH

Investigation of Insulin-Like Growth Factor (IGF)-I and Insulin Receptor Binding and Expression in Jejunum of Parenterally Fed Rats Treated with IGF-I or Growth Hormone¹

Department of Nutritional Sciences (D.M.N., D.J.H., M.B.G., K.R.K., E.M.D.), University of Wisconsin-Madison, Madison, Wisconsin 53706; and Department of Biochemistry (J.L.T., M.L.A.), University of Texas Health Science Center at San Antonio, San Antonio, Texas 78284

Address all correspondence and requests for reprints to: Denise M. Ney, Ph.D., Department of Nutritional Sciences, University of Wisconsin-Madison, 1415 Linden Drive, Madison, Wisconsin 53706. E-mail: ney{at}nutrisci.wisc.edu

To investigate the ability of insulin-like growth factor-I (IGF-I), but not GH, to stimulate jejunal growth, we compared indices of IGF-I and insulin receptor expression in jejunal membranes from rats maintained with total parenteral nutrition (TPN) and treated with rhIGF-I and/or rhGH. TPN without growth factor treatment (TPN control) induced jejunal atrophy, reduced serum IGF-I, increased serum insulin concentrations, and increased IGF-I receptor number, IGF-I receptor messenger RNA, and insulin-specific binding to 133% to 170% of the orally fed reference values, P < 0.01. Compared with TPN control, IGF-I or IGF-I + GH stimulated jejunal mucosal hyperplasia; IGF-I treatment increased serum IGF-I by 2- to 3-fold and decreased serum insulin concentrations by 60%, decreased IGF-I receptor number by 50% (P < 0.001), and increased insulin receptor affinity and insulin receptor protein content. Treatment with GH alone increased serum IGF-I concentration, did not alter TPN-induced jejunal atrophy, and decreased insulin-specific binding and insulin receptor protein content (39% and 59%, respectively, of the TPN control values, P < 0.01). We conclude that: 1) jejunal IGF-I receptor content reflects circulating concentration of ligand and is not limiting for jejunal growth; and 2) increased circulating concentration of IGF-I may promote jejunal growth via interaction with jejunal insulin or IGF-I receptors.

This article has been cited by other articles:

				P. E. Dube, K. J. Rowland, and P. L. Brubaker Glucagon-Like Peptide-2 Activates -Catenin Signaling in the Mouse Intestinal Crypt: Role of Insulin-Like Growth Factor-I Endocrinology, January 1, 2008; 149(1): 291 - 301. [Abstract] [Full Text] [PDF]

				E. M. Dahly, M. E. Miller, P. K. Lund, and D. M. Ney Postreceptor Resistance to Exogenous Growth Hormone Exists in the Jejunal Mucosa of Parenterally Fed Rats J. Nutr., March 1, 2004; 134(3): 530 - 537. [Abstract] [Full Text] [PDF]

				M. S. Chacko and M. L. Adamo Double-Stranded RNA Decreases IGF-I Gene Expression in a Protein Kinase R-Dependent, but Type I Interferon-Independent, Mechanism in C6 Rat Glioma Cells Endocrinology, February 1, 2002; 143(2): 525 - 534. [Abstract] [Full Text] [PDF]

				K. R. Kritsch, S. Murali, M. L. Adamo, and D. M. Ney Dexamethasone decreases serum and liver IGF-I and maintains liver IGF-I mRNA in parenterally fed rats Am J Physiol Regulatory Integrative Comp Physiol, February 1, 2002; 282(2): R528 - R536. [Abstract] [Full Text] [PDF]

				M. B. Gillingham, K. R. Kritsch, S. G. Murali, P. K. Lund, and D. M. Ney Resection upregulates the IGF-I system of parenterally fed rats with jejunocolic anastomosis Am J Physiol Gastrointest Liver Physiol, November 1, 2001; 281(5): G1158 - G1168. [Abstract] [Full Text] [PDF]

				L. Wang and M. L. Adamo Cyclic Adenosine 3',5'-Monophosphate Inhibits Insulin-Like Growth Factor I Gene Expression in Rat Glioma Cell Lines: Evidence for Regulation of Transcription and Messenger Ribonucleic Acid Stability Endocrinology, July 1, 2001; 142(7): 3041 - 3050. [Abstract] [Full Text] [PDF]

				M. S. Chacko and M. L. Adamo Double-Stranded Ribonucleic Acid Decreases C6 Rat Glioma Cell Numbers: Effects on Insulin-Like Growth Factor I Gene Expression and Action Endocrinology, October 1, 2000; 141(10): 3546 - 3555. [Abstract] [Full Text] [PDF]

				C. A. Peterson, M. B. Gillingham, N. K. Mohapatra, E. M. Dahly, M. L. Adamo, H. V. Carey, P. K. Lund, and D. M. Ney Enterotrophic Effect of Insulin-Like Growth Factor-I but not Growth Hormone and Localized Expression of Insulin-Like Growth Factor-I, Insulin-Like Growth Factor Binding Protein-3 and -5 mRNAs in Jejunum of Parenterally Fed Rats JPEN J Parenter Enteral Nutr, September 1, 2000; 24(5): 288 - 295. [Abstract] [PDF]