Rabbit placental clearing‐factor lipase and transfer to the foetus of fatty acids derived from triglycerides injected into the mother.

Elphick, Martin; Hull, D

doi:10.1113/jphysiol.1977.sp012105

Cited by 47 publications

(20 citation statements)

References 22 publications

Supporting

Mentioning

Contrasting

Order By: Relevance

“…However, it is thought that TG per se cannot cross the placenta, it has to be hydrolysed by lipases first, and studies in rabbits [18] and humans [19] have shown that fatty acids from TG infused into the mother are taken up by the placenta and released into the fetal circulation, whilst isotope studies in guinea pigs indicate that more of the fatty acid in the fetal circulation is obtained from maternal TG than NEFA [20]. Thus, it seems likely that the placenta utilises a mixture of TG and circulating NEFA but the relative importance of these sources of fatty acids in human pregnancy is not known.…”

Section: Discussionmentioning

confidence: 99%

Effect of Maternal Polyunsaturated Fatty Acid Concentration on Transport by the Human Placenta

Haggarty¹,

Ashton²,

Joynson³

et al. 1999

Neonatology

View full text Add to dashboard Cite

The role of the placenta in controlling the supply of fatty acids to the fetus was investigated in term placentas (n = 5) from normal pregnancies. The maternal side was perfused ex vivo for 90 min with a modified Krebs Ringer solution containing a physiological mixture of fatty acids – designed to mimic the composition of non-esterified fatty acids (NEFA) measured in the last trimester of pregnancy (n = 10) – and ratio of fatty acid to human albumin. The selectivity for α-linolenic acid (αLN) transfer to the fetal circulation was not significantly different from that observed when using the triglyceride (TG) composition (1.21 ± 0.04), but significantly different for AA (1.43 ± 0.12; p < 0.001) and docosahexaenoic acid (DHA; 2.02 ± 0.09; p = 0.048). The absolute rate of transfer (nmol · ml^–1) compared to that using the TG maternal perfusate composition was significantly different for LA (0.562 ± 0.038; p = 0.50), αLN (0.130 ± 0.009; p < 0.001), arachidonic acid (AA; 0.218 ± 0.022; p = 0.001) and DHA (0.383 ± 0.04; p < 0.001). Thus, placental selectivity for αLN and DHA appears to be relatively unresponsive to changes in the mixture of fatty acids in the maternal circulation but the selectivity for AA increased with the increase in the maternal AA concentration. For an 8-fold increase in the concentration of DHA in the maternal circulation there was a 13-fold increase in the transfer of DHA to the fetal circulation. For a 2-fold increase in the concentration of AA, transfer was increased 8-fold. For a 1.3-fold increase in the concentration of αLN, transfer was increased 2.1-fold. These results suggest that the maternal concentration of individual fatty acids, and hence the composition of the maternal diet, can have large effects on polyunsaturated/long-chain polyunsaturated fatty acids delivery to the fetus.

show abstract

Section: Discussionmentioning

confidence: 99%

Effect of Maternal Polyunsaturated Fatty Acid Concentration on Transport by the Human Placenta

Haggarty¹,

Ashton²,

Joynson³

et al. 1999

Neonatology

View full text Add to dashboard Cite

show abstract

“…VLDL-triglycerides are not transferred intact, but are first hydrolysed by an intracellular placental lipoprotein lipase [95,96]. Lipoprotein lipase activity has been demonstrated in the rat, rabbit and human placenta [97,98]. The rate of transfer of the derived fatty acids to the foetal circulation is limited by the rate of triglyceride lipolysis rather than by reesterification [96].…”

Section: Triglyceridesmentioning

confidence: 99%

Materno-foetal exchanges and utilisation of nutrients by the foetus: comparison between species

Père

2003

Reprod. Nutr. Dev.

View full text Add to dashboard Cite

-Several general features of nutrient uptake and utilisation by foetuses are similar among mammalian species. Nevertheless, there are also differences linked mainly to differences in placental permeability. Glucose and lactate are the main energetic substrates of the foetus. In normal conditions, the oxidation of carbohydrates accounts for about 75, 60 and 50% of oxygen uptake in the foetal pig, foal and lamb, respectively, and acetate accounts for about 10% in ruminants. Acidic amino acids are synthesised by the foetus, whereas neutral and basic amino acids are transported from the placenta. As shown by the high urea level in foetal blood, amino acids are partly involved in the oxidative metabolism of foetuses; their contribution is higher in ruminants than in humans, horses and pigs. Fatty acids cross the haemochorial placenta of rodents, rabbits and primates, and are incorporated into the foetal lipids, whereas their uptake by ruminant, pig and horse foetuses is very low.materno-foetal exchange / mammal / carbohydrate / fatty acid / amino acid

show abstract

“…An infusion of triacylglycerol emulsion (Intralipid, an emulsion of soya bean oil rich in C18:2 and C18:l) given i.v. to the pregnant rabbit appeared to be hydrolyzed by the placenta, allowing increased amounts of FFA to cross the placenta (28). Circulating triacylglycerols are bound to very low density lipoproteins and these authors also demonstrated within rabbit placenta the presence of lipoprotein lipase, an enzyme essential for the hydrolysis of circulating triacylglycerols.…”

Section: Discussionmentioning

confidence: 82%

“…(28,29). An infusion of triacylglycerol emulsion (Intralipid, an emulsion of soya bean oil rich in C18:2 and C18:l) given i.v.…”

Section: Discussionmentioning

confidence: 99%

Effect on Placental Transfer of Exogenous Lipid Administered to the Pregnant Rabbit

et al. 1995

View full text Add to dashboard Cite

ARSTR ACTThe transfer of lipids across the placenta was measured after infusion of an emulsion of triacylglycerol and phospholipid (Intralipid) into 10 anesthetized rabbits. Maternal and umbilical venous and arterial samples were collected at 10-min intervals. All samples were analyzed for concentration and fatty acid composition of FFA, triacylglycerol, and phospholipid fractions. At the end of the infusion period of Intralipid, there was a significant increase in the maternal concentrations of total triacylglycerol ( p < 0.01) and of total phospholipid ( p = 0.01) but not of total FFA ( p > 0.05). Maternal plasma triacylglycerol and phospholipid altered in composition to match that of the infused Intralipid by the end of the infusion. Despite the significant rise in maternal triacylglycerol and phospholipid concentrations, the umbilical vein-artery difference for these lipid fractions remained unchanged and very low. In contrast, the umbilical vein-artery difference for FFA (p < 0.02) rose gradually throughout the experiments. There was no significant change in the fatty acid composition of the maternal FFA, but the fatty acid composition of the umbilical vein-artery difference for FFA changed to reflect the composition of Intralipid. These experiments show that exogenous triacylglycerol and phospholipid dramatically alter the lipid fractions presented to the placenta in the maternal plasma but do not cross the placenta intact. However, the composition of the FFA crossing the placenta is modulated to become more similar to that of the exogenous lipid. (Pediatr Res 38: 1026-

show abstract

Rabbit placental clearing‐factor lipase and transfer to the foetus of fatty acids derived from triglycerides injected into the mother.

Cited by 47 publications

References 22 publications

Effect of Maternal Polyunsaturated Fatty Acid Concentration on Transport by the Human Placenta

Effect of Maternal Polyunsaturated Fatty Acid Concentration on Transport by the Human Placenta

Materno-foetal exchanges and utilisation of nutrients by the foetus: comparison between species

Effect on Placental Transfer of Exogenous Lipid Administered to the Pregnant Rabbit

Contact Info

Product

Resources

About