Fat transport in the body—changes in the lipoid content of the blood and lymph during fat absorption in the dog

After alimentary absorption of fat the content of both the total fatty acids and the phosphatides of the blood is increased. According to Bloor the phosphatides are synthesized from neutral fats by the blood corpuscles. It is also conceivable that phosphatide synthesis occurs during the passage of the fat components through the intestinal wall. To test this hypothesis the thoracic lymph and blood collected before and after introduction of olive oil into the duodenum of dogs previously starved for 18 hours was analyzed as follows:

The results show clearly that while the total fatty acids of the lymph increase rapidly during fat abslorption, the content of phosphatides remains unchanged. Hence there is no reason to believe that synthesis of phosphatides takes phce before the fat leaves the thoracic duct.