Gastric Emptying in Rats following Administration of a Range of Different Fats Measured as Acetaminophen Concentration in Plasma

Aim: To investigate the gastric emptying upon administration of ten different fats in order to determine whether major differences in fatty acid profiles resulted in differences in gastric emptying. Methods: Gastric emptying was measured as the appearance of acetaminophen in plasma which represents an indirect measure of gastric emptying. Emulsified fats with added acetaminophen were fed by gavage to rats, and the plasma concentration of acetaminophen was followed for 3 h by repeated blood sampling from the carotid artery. The fats administered included rapeseed, corn, and fish oils, lard, and cocoa butter as well as different structured lipids containing decanoic acid (10:0) and long-chain n-3 polyunsaturated fatty acids of marine origin. Overall, these fats had wide variations in fatty acid compositions and triacylglycerol structures. Results: No statistically significant differences were observed in gastric emptying between the groups fed the different fats, except for the emptying of tridecanoin (tri-10:0) that was statistically significantly slower than that of randomized oil, cocoa butter, and rapeseed oil (p < 0.05). The slower emptying of tri-10:0 could be caused by a lower caloric intake of this fat as compared with the other fats, because similar weights of fat were administered. Conclusion: The gastric emptying of fat was not influenced by fatty acid composition and triacylglycerol structure of the fats administered.