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) All Versions of this Article: 294/5/G1130    most recent 00400.2007v1 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 Web of Science Similar articles in PubMed Alert me to new issues of the journal Download to citation manager Citing Articles Citing Articles via HighWire Citing Articles via Web of Science (3) Citing Articles via Google Scholar Google Scholar Articles by Lu, W. J. Articles by Tso, P. Search for Related Content PubMed PubMed Citation Articles by Lu, W. J. Articles by Tso, P.

HORMONES AND SIGNALING

Using the lymph fistula rat model to study the potentiation of GIP secretion by the ingestion of fat and glucose

Departments of ¹Molecular and Cellular Physiology, ²Pathology, and ³Medicine, University of Cincinnati, Cincinnati, Ohio

Submitted 3 September 2007 ; accepted in final form 20 March 2008

Glucose-dependent insulinotropic polypeptide (GIP) is an important incretin produced in the K cells of the intestine and secreted into the circulating blood following ingestion of carbohydrate- and fat-containing meals. GIP contributes to the regulation of postprandial insulin secretion and is essential for normal glucose tolerance. We have established a method of assaying GIP in response to nutrients using the intestinal lymph fistula model. Administration of Ensure, a mixed-nutrient liquid meal, stimulated a significant increase in intestinal lymphatic GIP levels that were approximately threefold those of portal plasma. Following the meal, lymph GIP peaked at 60 min (P < 0.001) and remained elevated for 4 h. Intraduodenal infusions of isocaloric and isovolumetric lipid emulsions or glucose polymer induced lymph GIP concentrations that were four and seven times the basal levels, respectively. The combination of glucose plus lipid caused an even greater increase of lymph GIP than either nutrient alone. In summary, these findings demonstrated that intestinal lymph contains high concentrations of GIP that respond to both enteral carbohydrate and fat absorption. The change in lymphatic GIP concentration is greater than the change observed in the portal blood. These studies allow the detection of GIP levels at which they exert their local physiological actions. The combination of glucose and lipid has a potentiating effect in the stimulation of GIP secretion. We conclude from these studies that the lymph fistula rat is a novel approach to study in vivo GIP secretion in response to nutrient feeding in conscious rats.

insulin; diabetes; gastrointestinal hormone secretion; fat and glucose stimulation; glucose-dependent insulinotropic polypeptide

This article has been cited by other articles:

				S. M. Yoder, Q. Yang, T. L. Kindel, and P. Tso Stimulation of incretin secretion by dietary lipid: is it dose dependent? Am J Physiol Gastrointest Liver Physiol, August 1, 2009; 297(2): G299 - G305. [Abstract] [Full Text] [PDF]

				T. L. Kindel, Q. Yang, S. M. Yoder, and P. Tso Nutrient-driven incretin secretion into intestinal lymph is different between diabetic Goto-Kakizaki rats and Wistar rats Am J Physiol Gastrointest Liver Physiol, February 1, 2009; 296(2): G168 - G174. [Abstract] [Full Text] [PDF]

				A. Mittal, M. Middleditch, K. Ruggiero, C. M. Buchanan, M. Jullig, B. Loveday, G. J. S. Cooper, John. A. Windsor, and A. R. J. Phillips The proteome of rodent mesenteric lymph Am J Physiol Gastrointest Liver Physiol, November 1, 2008; 295(5): G895 - G903. [Abstract] [Full Text] [PDF]