Fetal lipoproteins and placental release of esterified lipids

1996 ◽  
Vol 8 (3) ◽  
pp. 457 ◽  
Author(s):  
JP Stammers ◽  
TJ Stephenson ◽  
JA Colley ◽  
D Hull
Keyword(s):  
Fatty Acid ◽  
Free Fatty Acid ◽  
Late Gestation ◽  
Free Fatty Acid Concentration ◽  
Fatty Acid Profiles ◽  
Rabbit Plasma ◽  
Albumin Solution ◽  
Series Of Experiments

An in vitro incubation technique was used to examine the release of lipids from the rabbit placenta. Free fatty acid, but not phospholipid or triacylglycerol, was released into the incubation media. In a second series of experiments, the addition of lipids to the umbilical circulation was studied in situ in the placenta of anaesthetized rabbits at late gestation. Each placenta was perfused from the fetal side in turn with two different perfusate solutions, either 4% bovine albumin solution or rabbit plasma. The rabbit plasma contained the appropriate carriers (lipoproteins) for esterified lipids, whereas the 4% albumin solution did not. The effluent perfusates were remarkably similar in free fatty acid concentration and composition, which closely matched the maternal free fatty acid profiles. The concentrations and fatty acid composition of the perfusate triacylglycerol and phospholipid fractions were unchanged by passage through the placenta, whether perfused with 4% albumin or with rabbit plasma. With this system, no evidence could be found for the addition of esterified lipids to the umbilical circulation in the rabbit despite the provision of appropriate carriers on the fetal side of the placenta.

scholarly journals Clearing-factor lipase in adipose tissue. A possible role of adenosine 3′,5′-(cyclic)-monophosphate in the regulation of its activity

1968 ◽  
Vol 109 (5) ◽  
pp. 841-849 ◽  
Author(s):  
D. R. Wing ◽  
D S Robinson
Keyword(s):  
Adipose Tissue ◽  
Fatty Acid ◽  
Free Fatty Acid ◽  
Cyclic Amp ◽  
Lipase Activity ◽  
Glucose Concentration ◽  
Free Fatty Acid Concentration ◽  
Epididymal Fat ◽  
Fat Bodies

1. The rise in clearing-factor lipase activity that occurs when epididymal fat bodies from starved rats are incubated in appropriate media in vitro is inhibited in the presence of 6-N-2′-O-dibutyryl-3′,5′-(cyclic)-AMP (1mm). 2. Inhibition occurs at a concentration of glucose in the incubation medium of 1·3mg./ml. or less, but not at a glucose concentration of 2·4mg./ml., unless caffeine (1mm), an inhibitor of 3′,5′-(cyclic)-nucleotide phosphodiesterase, is also present. Caffeine (5mm) alone inhibits the rise in clearing-factor lipase activity at a glucose concentration of 2·4mg./ml. of medium. 3. The concentration of free fatty acids in the epididymal fat bodies normally falls during incubations in vitro as the rise in clearing-factor lipase activity occurs. In the presence of 1mm-6-N-2′-O-dibutyryl-3′,5′-(cyclic)-AMP, however, either the tissue free fatty acid concentration is increased or it does not fall to the same extent. The concentration of glucose in the incubation medium is important in determining the direction and extent of the changes in tissue free fatty acid concentration that occur in the presence of 6-N-2′-O-dibutyryl-3′,5′-(cyclic)-AMP. 4. Free fatty acid concentrations in epididymal fat bodies in vivo rise as the clearing-factor lipase activity of the tissue falls during starvation. 5. The possibility that the concentration of 3′,5′-(cyclic)-AMP in adipose tissue may regulate clearing-factor lipase activity, and that the regulation may occur through effects of the nucleotide on tissue free fatty acid concentrations, is discussed.

scholarly journals Production of Endogenous Acetate by the Liver in Lactating Ewes

1976 ◽  
Vol 29 (2) ◽  
pp. 33 ◽  
Author(s):  
N D Costa ◽  
GH Mclntosh ◽  
AM Snoswell
Keyword(s):  
Fatty Acids ◽  
Fatty Acid ◽  
Free Fatty Acid ◽  
Free Fatty Acids ◽  
Venous Blood ◽  
Free Fatty Acid Concentration ◽  
Acetate Production ◽  
Hepatic Venous Blood ◽  
The Mean

The production of endogenous acetate by the liver has been investigated in lactating ewes using animals with indwelling arterial, and portal and hepatic venous cannulae. The capacity of the liver to produce acetate from acetyl-CoA in vitro has also been examined using homogenates prepared from liver biopsy samples. Mean arterial, portal and hepatic venous blood acetate concentrations in four ewes at 4 weeks lactation were 0'40, 1�00 and 1�46 mM respectively. The mean exogenous and endogenous acetate production rates were 56 and 54 mmol/h respectively, giving a total of 110 mrnol/h. The mean portal-hepatic venous difference in free fatty acid concentration was 81 11M. Converting this uptake of free fatty acids by the liver (based on palmitate as a standard) to 2-carbon equivalents, the acetate produced accounted for 70 % of the fatty acids taken up. The correlation coefficient (r2) between uptake of free fatty acids and production of acetate by the liver was o� 83 (P < O� 01),

Free fatty acid profiles of emulsified lipids during in vitro digestion with pancreatic lipase

2013 ◽  
Vol 139 (1-4) ◽  
pp. 398-404 ◽  
Author(s):  
Xianqian Zhu ◽  
Aiqian Ye ◽  
Timothee Verrier ◽  
Harjinder Singh
Keyword(s):  
Fatty Acid ◽  
Free Fatty Acid ◽  
Pancreatic Lipase ◽  
In Vitro Digestion ◽  
Fatty Acid Profiles

scholarly journals Free Fatty Acid Concentration and Carboxy methyl cellulase Activity of Some Formulas of Protected Fat-proteins Tested In Vitro

2015 ◽  
Vol 17 (2) ◽  
pp. 92
Author(s):  
Lilis Hartati ◽  
Ali Agus ◽  
Lies Mira Yusiati ◽  
Budi Prasetyo Widyobroto
Keyword(s):  
Fatty Acids ◽  
Fatty Acid ◽  
Free Fatty Acid ◽  
Acid Concentration ◽  
Palm Oil ◽  
Skim Milk ◽  
Fatty Acid Concentration ◽  
Free Fatty Acid Concentration ◽  
Second Stage

The aim of this study was to determine the levels of free fatty acids and carboxymethylcellulase activity (cmc-ase) activity of some protected fat-proteins base on in vitro Tilley and Terry method. Two sources of fat, i.e. crude palm oil and fish oil and three sources of protein i.e. skim milk, soybean flour and soybean meal were used in the formulation of protected fat-protein, and thus there were six treatment combinations. The filtrate from the in vitro test was analyzed for the levels of free fatty acids and  cmcase activity. The result of this research indicates that different combinations of feed materials and fat give different content of free fatty acid in first stage and second stage in vitro, with the best results in the combination treatment of skim milk and palm oil that give the lowest result of  free fatty acid concentration in fisrt stage in vitro (0.168%) and the highest result free fatty acid concentration in second stage in vitro ( 4.312%) . The activity of CMC-ase was not influenced by different  sources of fat and protein. It can be concluded was that the protection of the combination between skim milk and CPO gives the highest protection results.

scholarly journals The influence of melatonin on the production of free fatty acids by liver tissue in vitro

1989 ◽  
Vol 8 (4) ◽  
pp. 156-158
Author(s):  
F. A. Müller ◽  
J. M. C. Oosthuizen ◽  
I. Reyneke
Keyword(s):  
Fatty Acids ◽  
Fatty Acid ◽  
Free Fatty Acid ◽  
Free Fatty Acids ◽  
Acid Concentration ◽  
Liver Tissue ◽  
Fatty Acid Concentration ◽  
Free Fatty Acid Concentration ◽  
Stimulation Of

The separate and combined addition of insulin and melatonin to incubated liver slices produced an increase in the free fatty acid concentration in medium after incubation. Compared to insulin the addition of melatonin produced a more dramatic increase in medium free fatty acid concentration. The combined addition of insulin and melatonin have an additive effect on liver tissue in the production of free fatty acids. The increase in the free fatty acid concentration in incubation media is probably caused by stimulation of intracellular lipolysis by melatonin.

Apoprotein C effect on triglyceride transport in tandem-perfused rat hind end and liver

1984 ◽  
Vol 247 (3) ◽  
pp. G305-G310
Author(s):  
W. J. Kortz ◽  
J. R. Nashold ◽  
M. R. Greenfield ◽  
H. Hilderman ◽  
S. H. Quarfordt
Keyword(s):  
Fatty Acid ◽  
Free Fatty Acid ◽  
Fatty Acyl ◽  
Liver Fat ◽  
Molar Ratio ◽  
Perfusion System ◽  
In Vitro Perfusion ◽  
Arterial Inflow ◽  
High Concentrations

The metabolism of double-labeled triglyceride in a synthetic emulsion was defined in an in vitro perfusion system of rat hind end and liver described previously [Am. J. Physiol. 245 (Gastrointest. Liver Physiol. 8): G106-G112, 1983]. The metabolism of [3H]glycerol-[14C]triolein was defined in the absence of added apoproteins and with additions of human CII and both CII and CIII. Without apoprotein, a pronounced lipolysis of the triglyceride was recognized by high concentrations of radiolabeled glycerol and free fatty acid in the perfusate. The removal of an aliquot of hind-end venous effluent 5 min after adding the labeled triglyceride emulsion to the arterial inflow demonstrated a brisk lipolysis of the substrate when incubated outside the perfusion system. The addition of CII protein to the emulsion before its introduction into the tandem system eliminated perfusate lipolysis, both within the perfusion system and in incubations of aliquots withdrawn from the system. Intravascular lipolysis was not seen with triglyceride emulsions containing both CII and CIH or when an aliquot of hind-end venous effluent was incubated with triglycerides that had not been exposed to the perfusion system. The intravascular lipolysis observed for the [14C]triglyceride added to the tandem system without apoproteins was associated with relatively greater recoveries of 14C-fatty acyl in liver, fat, and muscle and relatively greater recoveries of 14CO2 than when CII alone or both CII and CIII were added with the triglyceride. The addition of CIII to CII in a 1:1 molar ratio increased the recovery of 14C-fatty acyl in muscle and the recovery as 14CO2.(ABSTRACT TRUNCATED AT 250 WORDS)

scholarly journals Effects of weight loss via high fat vs. low fat alternate day fasting diets on free fatty acid profiles

2015 ◽  
Vol 5 (1) ◽  
Author(s):  
Krista A. Varady ◽  
Vi T. Dam ◽  
Monica C. Klempel ◽  
Matthew Horne ◽  
Rani Cruz ◽  
...  
Keyword(s):  
Weight Loss ◽  
Fatty Acid ◽  
Free Fatty Acid ◽  
Fatty Acid Profiles ◽  
High Fat ◽  
Low Fat ◽  
Alternate Day Fasting
Sign in / Sign up

Export Citation Format

Share Document