The lymphatic transport of structured triacylglycerol consisting of medium and long chain fatty acids in rats has been investigated in several studies, but the following metabolism of the absorbed fatty acids carried in chylomicrons is less elucidated. In the present study we determined the transport of dietary C-13-labelled fatty acids in rat plasma to compare the chylomicron fatty acid metabolism after administration of specific structured, long chain and medium chain triacylglycerols. Rats were fed ML*M, M*LM*, L*L*L* or M*M*M* (L=linoleic acid, 18:2n-6, M=caprylic acid, 8:0, * = C-13-labelled fatty acid) by gavage. A maximum transport of 0.5% of the administered C-13-labelled 18:2n-6 was observed in 1mL rat plasma both after administration of L*L*L* and ML*M, while approximately 0.04% of the administered C-13-labelled 8:0 was detected in 1mL plasma following administration of M*M*M* or M*LM*. After L*L*L* administration C-13-labelled 20:4n-6 was observed in plasma, probably formed by elongation and desaturation of 18:2n-6 in the enterocyte or liver cells. Furthermore, C-13-labelled 16:0, 48:0, 18: 1n-9 and 20:4n-6 were observed in plasma of rats fed M*M*M* and M*LM* due to transformation to long chain fatty acids in the enterocyte and/or the liver. The present study indicates similar chylomicron metabolism of specific structured triacylglycerols compared with long chain or medium chain triacylglycerols and reveals information of elongation and desaturation of the dietary fatty acids.
|Publication status||Published - 2004|