We have used a classical neurotransmitter release model to investigate the effect of dietary polyenoic fatty acids on the sensitivity of the presynaptic dopamine autoreceptor in slices of cat caudate nucleus. Maximum inhibition of [3H]dopamine release was seen only in animals fed a diet containing post delta-6-desaturation fatty acids of ...

To examine whether the typical nightly rise of nonesterified fatty acids in high yielding dairy cows is due to enhanced sympathoadrenal activity, the beta-adrenergic blocker, propranolol, was infused from 1800 to 0805 h. Concentrations of nonesterified fatty acids continuously increased, whereas those of glucose and insulin decreased. Nonesterified fatty acid ...

Stimuli-induced changes in free fatty acid levels of activated platelets were assayed by reversed-phase high performance liquid chromatography. The fatty acids were prelabeled as their fluorescent 9-aminophenanthrene derivatives for the detection. The levels of saturated fatty acids such as palmitic acid in an extracellular medium of rat platelet-rich plasma are ...

Adipocytes incubated with adenosine deaminase (ADA) showed: (1) increased amounts of fatty acids in the medium; (2) increased glucose incorporation into acylglycerol glycerol; (3) decreased glucose incorporation into acylglycerol fatty acids; (4) a co-ordinate decrease in the sensitivity of lipolysis and glucose incorporation into acylglycerol to insulin; (5) similar effects ...

A classical neurotransmitter release model was used to investigate the effect of the limitation of dietary polyenoic fatty acids on the function of presynaptic dopamine autoreceptors in slices from the caudate nucleus of kittens (juvenile domestic cats). Maximum inhibition of 3H-dopamine release was detected only in the brains of animals ...

Release of free fatty acids from rat cerebral synaptosomes, synaptic plasma membranes and mitochondria was studied under in vitro hypoxia. The release increased in the absence of oxygen. Removal of calcium ions from the medium suppressed the release. These trends were similar in every subcellular fraction tested. The data imply ...

Myocardial substrate preferences following cardioplegic arrest for coronary bypass surgery have not been established. Fatty acids are believed to be the major fuel source for aerobic metabolism. Following cardioplegic arrest arterial fatty acid levels are elevated and myocardial fatty acid accumulation without oxidation may contribute to reperfusion injury. Perioperative fatty ...

Studies are reported on microbial conversion of various unsaturated fatty acids to 10-hydroxy and/or 10-oxo fatty acids by Micrococcus luteus. Four fatty acids possessing cis-9-unsaturation produced 10-hydroxy and 10-oxo fatty acid products, but three enoic acids possessing trans-9-unsaturation or double bond(s) in other than the 9-carbon position were inactive as ...

The composition of fatty acids in serum lipids has been shown to reflect the quality of dietary fat. In order to examine the long-term stability (tracking) of the serum (and hence dietary) fatty acid composition serum cholesteryl ester fatty acids were analysed by gas chromatography in a randomly selected population ...

The growth of hormone-dependent breast cancer cell lines (MCF7 and T47D) is inhibited in vitro by progestins which also induce several proteins. We have cloned cDNA sequences corresponding to one of them, a 250-kDa protein, and have shown that the corresponding mRNA is also rapidly induced by progestins (Chalbos D., ...

Dispersed epithelial cells from lactating bovine and goat mammary glands incorporated acetate into all fatty acids (C4 to C16) that were incorporated into mainly triacylglycerols. The cells secreted free fatty acids only into the incubation medium, and this secretion was dependent on the concentration of albumin and the type and ...

The relative contributions of esterified and non-esterified fatty acids to placental lipid transfer were estimated in 7 pregnant guinea-pigs. The fetal side of the placenta was perfused in situ whilst a constant infusion of a mixture of [3H]triacylglycerol emulsion (Intralipid) and [14C]non-esterified fatty acid was given i.v. to the anaesthetised ...

Staphylococcus aureus, Staphylococcus hyicus, Streptococcus agalactiae, and Corynebacterium bovis were tested for sensitivity to long-chain fatty acids predominant in teat canal keratin. Antibacterial activity of free fatty acids on each bacterial species was measured after 12 and 24 h in chemically defined media. Polyene C18:2 and C18:3 acids were bactericidal ...

The presence of covalently bound fatty acids in the insulin receptor has been explored in cultured human (IM-9) lymphocytes. Both alpha (Mr = 135,000) and beta (Mr = 95,000) subunits of the receptor incorporate [3H]myristic and [3H]palmitic acids in a covalent form. The effects of alkali and hydroxylamine on the ...

The effects of fatty acids on the ionic currents of the voltage-clamped squid giant axon were investigated using intracellular and extracellular application of the test substances. Fatty acids mainly suppress the Na current but have little effect on the K current. These effects are completely reversed after washing with control ...

Between 1955-1960 it was realized that the fatty acids circulating in the blood, after transport into the cardiac cells, then beta-oxidation in the myocyte mitochondria, were the major source of energy behind the impressive hydraulic performance of the heart. Only albumin-bound fatty acids and, to a lesser extent, cholesterol ester ...

The endogenous prostanoid synthesis can principally be influenced by a variation of the polyunsaturated fatty acid supply in food. Withholding an essential fatty acid supply in food for a length of time results in a low rate of formation of prostanoids. However, there is no simple correlation between the amount ...

The content of non-esterified fatty acids (NEFA) and their CoA and carnitine esters is low in normoxic cardiac tissue. The majority of fatty acids is esterified in the triacylglycerol and phosphoglyceride pool. During myocardial ischaemia beta-oxidation of fatty acids is inhibited. In addition, turnover of the esterified fatty acid pools ...

It is now clear that a wide variety of differentiated cells in culture exhibit essentially the full spectrum of mammalian fatty acid metabolism. These cells readily incorporate free fatty acids into membrane phosphoglycerides, modify exogenous fatty acids by desaturation and elongation, and store excess fatty acyl groups, primarily as triacylglycerols. ...

Normal myocardial function is dependent on aerobic energy production. A wide variety of substrates, including free fatty acids, glucose, lactate and ketone bodies, may be used in the myocyte. Anaerobic metabolism is not sufficient to produce enough energy to maintain the normal concentration of high energy phosphates in the myocytes ...

The placental transfer of non-esterified fatty acids, predominantly in the direction of mother to fetus, is regulated on a gross scale by the transplacental non-esterified fatty acid gradient. This is maintained by fetal liver lipid uptake and by enhanced lipolysis of circulating triacylglycerol in the pregnant mother. It is also ...

Data on market size, market share, and compositional changes of various products made from partially hydrogenated fats and oils were used to estimate current, previous, and predicted levels of trans fatty acids in the US diet. Recent literature and various perceptions of the toxicological, physiological, and nutritional effects of trans ...

Uptake of Tween-fatty acid esters and incorporation of the fatty acids into lipids by soybean (Glycine max [L.] Merr.) suspension cultures was investigated, together with subsequent turnover of the incorporated fatty acids and associated changes in endogenous fatty acid synthesis. Tween uptake was saturable, and fatty acids were rapidly transferred ...

Primary cultures of adult rat hepatocytes were used to compare the uptake and esterification of essential polyunsaturated fatty acids (18:2, 20:3 and 20:4 of the n-6 series) with those of palmitic and oleic acids. The uptake of unesterified fatty acids was linearly related to the free fatty acid/albumin molar ratio ...

Homogenates of trypomastigotes of Trypanosoma cruzi (T.c) exhibited low-potency cytotoxic activity toward neuroblastoma cells. The cytotoxic activity was markedly decreased after preservation for 1 week, even at -20 degrees C. Trypsin and pronase E were shown to effectively enhance or restore the cytotoxic activity of T.c by producing some alteration ...

The lipoxygenase from reticulocytes oxygenates 15LS-HETE to 8-hydroperoxy-15-hydroxy-5,9,11,13-eicosatetraenoic acid and 5-hydroperoxy-15-hydroxy-6,8,11,13-eicosatetraenoic acid only in the presence of catalytic concentrations of monohydroperoxy fatty acids. During this reaction the hydroperoxy fatty acids are converted to more polar products including hydroxy fatty acids. From kinetic measurements of 15LS-HETE oxygenation it was calculated that ...

The content of the free fatty acids and the fatty acids of triacylglycerols has been measured in human plantar stratum corneum from normal and hyperkeratotic subjects with palmoplantar keratoderma. Fatty acids of triacylglycerols in normal tissues showed a characteristic pattern with a relative abundance of short-chain length and unsaturated fatty ...

The low pH-dependent fusion of lipid membranes induced by two types of the fatty acylated influenza viral hemagglutinin has been studied by use of an energy transfer assay. When protein bound fatty acids were released from the hemagglutinin by hydroxylamine treatment viral fusion activity was inhibited. The extent of fusion ...

The objective of this work was to examine the mechanism by which dietary saturated fatty acids, as compared with polyunsaturated fatty acids, lower hormone-sensitive lipolysis in rat adipocytes. Rats were fed a purified diet containing 14% of a fat with a high concentration of either saturated fatty acids (coconut oil ...

Mixed micelles of bile salt and phospholipids inhibit the lipase-colipase-catalysed hydrolysis of triacylglycerols. Free fatty acids can reverse this inhibition and reactivate lipase-colipase. This reactivation is either due to the formation of a high-affinity complex between lipase and colipase induced by free fatty acids and/or to a change of the ...

To determine the amount of isomeric fatty acids in the diets of a segment of the American population, daily food intake was collected, using the duplicate portion method, from eight healthy white adolescent girls for 7 days. The fifty-six diets were analyzed for fatty acids by gas-liquid chromatography. The amount ...

The rates of synthesis of fatty acid synthase and the levels of its mRNA are high in livers of chicks, ducklings, or goslings fed high-carbohydrate mash diets and low in livers of starved birds, indicating pretranslational regulation of fatty acid synthase activity. Determination of the step(s) at which the nutritional ...

The dietary effects of the trans fatty acids in hydrogenated fats in health and disease deserves consideration for at least two reasons. One, trans fatty acids are becoming increasingly important as a source of calories in all industrialized countries, and two, their structural differences from the fatty acids in unhydrogenated ...

Free fatty acids in sebum arise from lipolytic action of bacterial lipases. We have demonstrated an inhibitory effect of zinc on the lipase of the three Propionibacterium species found in human pilosebaceous follicles. We were also able to show a small corresponding fall in the free fatty acid content of ...

The physical properties of polyunsaturated and saturated fatty acids are compared in relation to melting points and fluidity. The role of polyunsaturated fatty acids on membrane fluidity and membrane bound enzyme activity is discussed. The influence of the environment, particularly temperature, on poikilothermic animals is considered in relation to membrane ...

To investigate the feasibility of radioiodinated free fatty acids for 'metabolic imaging', the kinetics and distribution pattern of metabolites of 131I-heptadecanoic acid were studied in canine myocardium throughout metabolic interventions. In control dogs and in dogs during glucose/insulin and sodium lactate infusion, biopsy specimens were taken during a 90-min period ...

Meconium samples of 20 healthy full-term babies were analyzed for free fatty acid content. The total fatty acid content per net weight varied by as much as 9-fold between samples. Considerable variability was also observed in the individual fatty acids found in each sample. Palmitic, stearic and oleic acids were ...

The development of fatty acids labelled with iodine-123 is reviewed. The variety of methods for producing 123I and introducing radioiodine into the molecule is discussed and the important points of the biochemical background are recalled with the aim of finding a broad application for 123I-labelled fatty acids. The results of ...

Alkyldihydroxyacetonephosphate synthase (alkyl-DHAP synthase) catalyzes the exchange of the ester-linked fatty acid of 1-O-acyldihydroxyacetone phosphate (1-O-acyl-DHAP) for a fatty alcohol that is attached in an ether linkage to form 1-O-alkyldihydroxyacetone phosphate (1-O-alkyl-DHAP). In our continuing investigation of the mechanism of this enzyme, we have examined the fatty acid released during ...

During 1980 and 1982, 164 men aged 45-54 in North Edinburgh and West Fife participated in a 7-day individual weighed dietary survey. The mean energy intake was 11.2 MJ (2700 kcal), 38.1 per cent of which came from fat and 6.7 per cent from alcohol. The P:S ratio was 0.30 ...

A correlation between the rate of H+/Ca2+ exchange and the content of free fatty acids in mitochondria has been found. Fatty acids were isolated from mitochondria with different activities of H+/Ca2+ exchange. It has been shown that these free fatty acids are able to induce Ca2+ release in exchange to ...

Interphotoreceptor retinoid-binding protein (IRBP) purified from monkey interphotoreceptor matrix contains relatively high concentrations of endogenous fatty acids, 6.51 mol/mol of protein. Sixty-five percent of the total fatty acid bound to IRBP was found to be noncovalently attached, with the remainder covalently bound. The fatty acids are not residual components of ...

After periods of 5 and 30 min following decapitation, rat cerebral cortices were removed and subcellular fractions were prepared. Fractions P1A (large myelin), P1B (nuclei), P1C (cells and debris), P2A (small myelin), P2B (synaptosomes), P2C (mitochondria), and P3 (microsomes) were isolated. Free fatty acid levels of 1.0 and 1.4 mumol/g ...

We have studied the reproducibility of myocardial extraction ratios of lactate, glucose and free fatty acids in patients with stable angina during atrial pacing. Two pacing periods, separated by an interval of 45 min, were imposed. The individual data were highly reproducible for lactate. Mean values for glucose and for ...

Hepatic fatty infiltration sonographically appears as an area of increased echogenicity. When focal areas of fat are present in otherwise normal liver parenchyma, the fatty area may be masslike in appearance, leading to further imaging evaluation and sometimes even biopsy. This article discusses seven patients with focal fatty infiltration, who ...

We have previously reported that anionic phospholipids (Philipson, K.D., and Nishimoto, A.Y. (1984) J. Biol. Chem. 259, 16-19) and other anionic amphiphiles (Philipson, K.D. (1984) J. Biol. Chem. 259, 13999-14002) stimulate Na+-Ca2+ exchange in cardiac sarcolemmal vesicles. To further these studies, we have now investigated the effects of a variety ...

In an open chested dog model utilizing dual isotope techniques (125I heptadecanoic acid and 9, 10 3H palmitic acid), sequential myocardial biopsies were performed to: validate the scintigraphic background subtraction technique for the iodo fatty acid, compare the myocardial activity time course for the fatty acids and by TLC methods ...

Lysolecithin exhibited bactericidal effect on mycobacteria and staphylococci, but not on E. coli. The effect on staphylococci was manifested shortly after exposure, but that on mycobacteria was of the delayed type. The mycobactericidal activity was dependent on the fatty acid moiety of the chemical structure reflecting the cytotoxicity of the ...

Structural variations in the carbon chain of free fatty acids influence the uptake of free fatty acids in the myocardium. To enable the use of free fatty acids in nuclear cardiology, various methods of introducing gamma-emitting isotopes have been evaluated. The uptake of various free fatty acids is described and ...

We have investigated the interaction of crotoxin (component A-component B complex) and of its isolated phospholipase subunit (component B) with hydrophobic compounds by ESR, using spin-labeled fatty acids as probes. The phospholipase subunit alone (component B) binds more than three labeled fatty acid molecules/molecule with different affinities, the highest corresponding ...