Contribution of circulating maternal lipids to fetal tissues in the guinea pig.
Using a constant infusion of [1-14C] palmitic acid into 7 late pregnant guinea-pigs the contribution of circulating maternal lipid to the fetuses was assessed. Within the mother plasma radioactivity was found mainly in free fatty acid with only a small amount circulating as triacylglycerol. In contrast in the fetal plasma [14C] was distributed as one-quarter free fatty acid and three-quarters triacylglycerol, with total [14C] levels being four-fold higher than in the maternal plasma after 160 min of infusion. [14C] Triacylglycerol was found in the fetal liver within 10 min of commencing infusion and levels rose to 12 times the levels of [14C] triacylglycerol in the fetal plasma (per/g or ml) by 100-160 min. [14C] Distribution into the lipid moieties of fetal tissues was found to change with time. By 100-160 min the distribution was: liver, triacylglycerol 83%, phospholipid 7%, free fatty acid 4%; fat, triacylglycerol 80%; heart, triacylglycerol 38%, phospholipid 33%, free fatty acid 9%; kidney, triacylglycerol 15%, phospholipid 58%, free fatty acid 10%; muscle, triacylglycerol 70%, phospholipid 10%, free fatty acid 10%; lung, phospholipid 75%; brain, phospholipid 80%. It was concluded that free fatty acid transferred from the mother contributes substantially to fetal lipids in late gestation in this species.
D000818:Animals; D005230:Fatty Acids, Nonesterified / Q000097:blood; D005260:Female; D006168:Guinea Pigs; D008055:Lipids / Q000097:blood*; D008431:Maternal-Fetal Exchange; D010169:Palmitic Acids / Q000097:blood; D011247:Pregnancy; D014018:Tissue Distribution; D014280:Triglycerides / Q000097:blood
D005230:Fatty Acids, Nonesterified; D008055:Lipids; D010169:Palmitic Acids; D014280:Triglycerides