Slow absorption of conjugated linoleic acid in rat intestines, and similar absorption rates of 9c,11t-conjugated linoleic acid and 10t,12c-conjugated linoleic acid

• Published in: Bioscience, biotechnology, and biochemistry Vol. 71; no. 8; pp. 2034 - 2040
• Main Authors: Tsuzuki, T.(Miyagi Univ., Sendai (Japan). School of Food, Agricultural and Environmental Sciences), Ikeda, I
• Format: Journal Article
• Language: English
• Published: Tokyo Japan Society for Bioscience, Biotechnology, and Agrochemistry 01-08-2007; Japan Society for Bioscience Biotechnology and Agrochemistry; Oxford University Press
• Subjects: ABSORCION DIGESTIVA; absorption; ABSORPTION DIGESTIVE; ACIDE LINOLEIQUE; ACIDO LINOLEICO; Animals; Biological and medical sciences; conjugated fatty acid; conjugated linoleic acid; DIGESTIVE ABSORPTION; Fundamental and applied biological sciences. Psychology; INTESTIN; Intestinal Absorption; INTESTINES; INTESTINOS; Kinetics; LINOLEIC ACID; Linoleic Acids, Conjugated - metabolism; lymph; Lymph - metabolism; RAT; RATA; RATS; Thoracic Duct; Conjugated linoleic acid; Vertebrata; lymph; Mammalia; Absorption; Rat; Rodentia; conjugated fatty acid; Fatty acids; Linoleic acid
• ISSN: 0916-8451; 1347-6947
• DOI: 10.1271/bbb.70238

We have previously shown that the 9c,11t-conjugated linoleic acid (CLA) concentration was always significantly higher than the 10t,12c-CLA concentration following the administration of these compounds to mice and rats, and considered that structural differences between the conjugated double bonds in these isomers affected absorption in the small intestine. This study investigates the absorption of CLA in the rat intestine by a lipid absorption assay of lymph from the thoracic duct. In Study 1, we used safflower oil and a triacylglycerol form of CLA (CLA-TG), while in Study 2, we used 9c,11t-CLA and 10t,12c-CLA. The cumulative recovery of CLA was lower than that of linoleic acid until two hours after sample administration. There was no difference in the extent of lymphatic recovery of 9c,11t-CLA and 10t,12c-CLA after the administration of CLA-TG, 9c,1lt-CLA, and 10t,12cCLA to the rats, suggesting that geometrical and positional isomerism of the conjugated double bonds did not influence the absorption.