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1.
Comparative studies on composition of cardiac phospholipids in rats fed different vegetable oils 总被引:5,自引:5,他引:0
J. K. G. Kramer 《Lipids》1980,15(9):651-660
Male Sprague-Dawley rats were fed diets for 1 or 16 weeks, containing 20% by weight vegetable oils differing widely in their
oleic, linoleic and linolenic acid content. No significant changes were observed in the level of the cardiac lipid classes.
The fatty acid composition of the 2 major phospholipids, phosphatidylcholine and phosphatidylethanolamine, showed a remarkable
similarity between diets in the concentration of total saturated, C22 polyunsaturated and arachidonic acids. Monounsaturated
acids were incorporated depending on their dietary concentration, but the increases were moderate. Dietary linolenic acid
rapidly substituted C22 polyunsaturated fatty acids of the linoleic acid family (n−6) with those from the linolenic acid family
(n−3). The results suggest that dietary linolenic acid of less than 15% does not inhibit the conversion of linoleic to arachidonic
acid but the subsequent conversion of arachidonic acid to the C22 polyunsaturates was greatly reduced. Significant amounts
of dietary monounsaturated fatty acids were incorporated into cardiac cardiolipin accompanied by increases in polyunsaturated
fatty acids, apparently to maintain an average of 2 double bonds/molecule. The cardiac sphingomyelins also accumulated monounsaturated
fatty acids depending on the dietary concentration. It is quite evident from the results of this study that the incorporation
of oleic acid and the substitution of linolenic for linoleic acid-derived C22 polyunsaturated fatty acids into cardiac phospholipids
was related to the dietary concentration of these fatty acids and was not peculiar to any specific oil. Even though it is
impossible to estimate the effect of such changes in cardiac phospholipids on membrane structure and function, results are
discussed which suggest that the resultant membrane in the Sprague-Dawley male rat is more fragile, leading to greater cellular
breakdown and focal necrosis.
Contribution No. 914 from the Animal Research Institute. 相似文献
2.
C. R. Cavaglieri Felippe P. C. Calder M. G. Vecchia M. R. Campos J. Mancini-Filho E. A. Newsholme R. Curi 《Lipids》1997,32(6):587-591
The effect of oat bran-(OBD) and wheat bran-enriched diets (WBD) on fatty acid composition of neutral lipids and phospholipids
of rat lymphocytes and macrophages was investigated. In neutral lipids of lymphocytes, OBD reduced the proportion of palmitoleic
acid (48%), whereas WBD reduced by 43% palmitoleic acid and raised oleic (18%), linoleic (52%), and arachidonic (2.5-fold)
acids. In neutral lipids of macrophages, OBD increased palmitic (16%) and linoleic (29%) acids and slightly decreased oleic
acid (15%). The effect of WBD, however, was more pronounced: It reduced myristic (60%), stearic (24%) and arachidonic (63%)
acids, and it raised palmitic (30%) and linoleic (2.3-fold) acids. Neither OBD nor WBD modified the composition of fatty acids
in phospholipids of lymphocytes. In contrast, both diets had a marked effect on composition of fatty acids in macrophage phospholipids.
OBD raised the proportion of myristic (42%) and linoleic (2,4-fold) acids and decreased that of lauric (31%), palmitoleic
(43%), and arachidonic (29%) acids. WBD increased palmitic (18%) and stearic (23%) acids and lowered palmitoleic (35%) and
arachidonic (78%) acids. Of both cells, macrophages were more responsive to the effect of the fiber-rich diets on fatty aicd
composition of phospholipids. The high turnover of fatty acids in macrophage membranes may explain the differences between
both cells. The modifications observed due to the effects of both diets were similar in few cases: an increase in palmitic
and linoleic acids of total neutral lipids occurred and a decrease in palmitoleic and arachidonic acids of phospholipid. Therefore,
the mechanism involved in the effect of both diets might be different. 相似文献
3.
Jen-sie Tou 《Lipids》1989,24(9):812-817
This study extended the earlier finding that platelet-activating factor (1-O-alkyl-2-acetyl-sn-glycero-3-phosphocholine) promotes arachidonic acid incorporation into neutrophil phosphatidylinositol (PI) and phosphatidylcholine
(PC). In the present study the effect of PAF on fatty acid uptake by human neutrophils and the incorporation of extracellular
linoleic acid and palmitic acid into phospholipids were investigated. Incubation of 10−7 M PAF with neutrophils and radiolabeled arachidonic acid or linoleic acid or palmitic acid for 1–10 min resulted in an increased
rate of loss of label from the incubation medium. PAF stimulated the incorporation of linoleic acid and palmitic acid most
significantly into PI and PC. The magnitude of stimulation was greater in PI than in PC for the incorporation of linoleic
acid, and vice versa for the incorporation of palmitic acid. The positional distribution of linoleic acid and palmitic acid
in PI and PC and the mass of these phospholipids were not altered in PAF-stimulated neutrophils. An increased incorporation
of all three fatty acids into both diacyl and alkylacyl species of PC was demonstrated after a two minute incubation of cells
with PAF. While more radioactivity was recovered in the diacyl species, the magnitude of increase of radioactivity in the
alkylacyl species was more pronounced than that in the diacyl species of PC. These results suggest that both increased fatty
acid uptake and increased available lysophospholipids may be contributory to the increased phospholipid acylation induced
by PAF. 相似文献
4.
The lipid composition of Morris hepatoma 5123c was analyzed together with that of liver and blood plasma from both normal
and tumor-bearing rats. The results showed that the liver of tumor-bearing rats contained higher amounts of glycerides, cholesteryl
esters, free fatty acids and phospholipids than the liver of normal rats. In the blood plasma of tumor-bearing rats, there
was an increase of free cholesterol and triglycerides; this latter difference, however, was not statistically significant.
Acyl chain changes in the liver of tumor-bearing rats consisted of an increase of palmitic and oleic acids and a decrease
of stearic and arachidonic acids in phosphatidylinositol. Morris hepatoma 5123c contained a lower amount of triglycerides
than the livers (both host and normal) and showed a significant decrease of total phospholipids when compared to the host
liver. The major acyl chain changes found in Morris hepatoma 5123c compared with both normal and host rat livers were: a)
a higher percentage of arachidonic acid together with a lower proportion of palmitic acid in cholesteryl esters; b) an increase
of stearic and arachidonic acids and a decrease of palmitic acid in triglycerides; and c) a higher level of palmitic and oleic
acids associated with a lower percentage of stearic and C22 polyunsaturated acids in phosphatidylcholine. 相似文献
5.
The fatty acid composition of the phospholipids of sarcoplasmic reticulum preparations from rabbit psoas (white) and soleus
(red) muscles was determined. The sarcoplasmic reticulum from psoas muscle was lower in stearic and oleic acids and higher
in palmitic and linoleic acids than that from soleus muscle, and contained a greater proportion of polyunsaturated fatty acids.
However most of the differences in fatty acids were small. 相似文献
6.
Behaviour of Free Fatty Acids After Burning in Animal Experiments The pattern of free fatty acids in the serum of rats after 20% burning was determined in order to elucidate the severe changes resulting from the shock after burning. Gas chromatographic analysis was carried out after 1/2, 1, 6, 24, 48 and 72 hours following burning trauma. For comparison the fatty acid pattern of a control group of unburned animals was examined. Gas chromatographic analysis showed following characteristic changes: 1. An increase of palmitic, stearic, palmitoleic, oleic, linoleic and linolenic acids after 6 hours following burning. 2. A constant level of palmitic acid even after 72 hours. 3. A slight decline of palmitoleic and oleic acids after 48 and 72 hours. 4. An increase of the polyunsaturated linoleic and linolenic acids till 24 hours after burning and a subsequent large decrease. The function of fatty acids, especially linoleic and linolenic acids, as constituents of membranes is of great importance. They determine essentially the membrane permeability. Moreover, the polyunsaturated fatty acids are precursors of prostaglandins, whose role in burning is little investigated. The characteristic change of polyunsaturated fatty acids suggests a relationship with membrane damage, increased thrombocyte aggregation and alterations of lung surfactant. Their steep decline might be caused by autoxidation due to lack of antioxidants, degradation during conversion to energy and incorporation into lipoproteins and membranes. The significance of free fatty acids in catabolism of the cell in severe trauma is unquestionable. 相似文献
7.
Dexamethasone depresses Δ6 and Δ5 and increases Δ9 desaturase and synthase activities. Therefore, we investigated the effect
on the fatty acid composition of microsomal liver lipids and phosphatidylcholine (PtdCho) molecular species. After 15 d of
treatment we found a notable decrease in arachidonic acid, a small decrease in stearic acid, and increases of linoleic, oleic,
palmitoleic, and palmitic acids in liver microsomal total lipids and PtdCho. The study of the distribution of the PtdCho molecular
species indicated that 18∶0/20∶4n−6, 16∶0/20∶4n−6, and 16∶0/18∶2n−6 predominated in the control animals. Dexamethasone, as
expected because of its depressing effect on arachidonic acid synthesis and activation of oleic and palmitic acid synthesis,
evoked a very significant decrease in 18∶0/20∶4n−6 PtdCho (P<0.001) and an important increase in 16∶0/18∶2n−6. The invariability of 16∶0/20∶4n−6 PtdCho could be related to the antagonistic
effect of arachidonic and palmitic acid synthesis. PtdCho species containing oleic acid were not significant. The bulk fluidity
and dynamic properties of the microsomal lipid bilayer measured by fluorometry using the probes 1,6-diphenyl-1,3,5-hexatriene
and 4-trimethylammonium-phenyl-6-phenyl-1,3,5-hexatriene showed no significant modification, probably owing to a compensatory
effect of the different molecular species, but changes of particular domains not detected by this technique are possible.
However, the extremely sensitive Laurdan detected increased lipid packing in the less-fluid domains of the polar-nonpolar
interphase of the bilayer, possibly evoked by the change of molecular species and cholesterol/phospholipid ratio. The most
important effect found is the decrease of arachidonic acid pools in liver phospholipids as one of the corresponding causes
of dexamethasone-dependent pharmacological effects. 相似文献
8.
The fatty acid patterns of rat liver mitochondrial and microsomal phospholipids were analyzed from term fetuses, 1 and 4 days
old, and adult rats. The main fatty acids of phosphatidylethanolamine and-choline were stearic and palmitic acids, although
the patterns differed slightly. The fatty acid composition of corresponding phospholipids in mitochondria and microsomes was
similar. The fatty acid pattern of cardiolipin was dominated by linoleic acid. The most consistent feature of the developmental
changes in the fatty acid patterns of all phospholipids studied was a decrease in the relative amount of monounsaturated fatty
acids. The percentages of saturated fatty acids in phosphatidyl-ethanolamine and-choline increased during neonatal development.
It is suggested that the high levels of fetal monounsaturated fatty acids were due to low availability of polyunsaturated
fatty acids. 相似文献
9.
Teruyoshi Yanagita Mikinobu Satoh Hisashi Nomura Noriyuki Enomoto Michihiro Sugano 《Lipids》1987,22(8):572-577
Effects of di-(2-ethylhexyl)adipate (DOA) and di-(2-ethylhexyl)phthalate (DEHP), plasticizers for polyvinylchloride products,
on concentrations and compositions of hepatic phospholipids were studied in rats. When administered to rats at a 2% level
for 2 wk, both DOA and DEHP caused a hepatomegaly, an increase in hepatic phospholipids and a decrease in the ratio of phosphatidylcholine
(PC) to phosphatidylethanolamine (PE). In the comparable study with mice, the alkyl moiety of DOA was found to be responsible
for these alterations. DOA and DEHP specifically altered fatty acid compositions of PC and PE: there was an increase in oleic
and palmitic acids and a decrease in stearic and docosahexaenoic acids in PC and an increase in arachidonic acid at the expense
of docosahexaenoic acid in PE. In addition, DOA caused an increase in the trienoic and tetraenoic molecular species in PC
and an increase in the 1-palmitoyl-2-arachidonyl (16∶0//20∶4) species in PE. Thus, the effects of DOA on the lipid dynamics
resembled those observed with DEHP, although the magnitude was slightly moderated. 相似文献
10.
The fatty acid composition of erythrocytes, platelets, and serum lipids was compared between subjects who had been eating
a strict uncooked vegan diet (“living food”) for years and omnivore controls. The vegan diet contains equal amounts of fat
but more monounsaturated and polyunsaturated and less saturated fatty acids than the mixed diet of the control group. In vegans,
the proportion of linoleic acid was greater in all lipid fractions studied. Also, the levels of other n−6 fatty acids were
greater, with the exception of arachidonic acid levels, which were similar in most fractions. In erythrocytes, platelets and
serum phospholipid fractions, this increase was mainly at the expense of the n−3 fatty acids. The proportions of eicosapentaenoic
and docosahexaenoic acid were only 29–36% and 49–52% of those in controls, respectively. In vegans the ratio of n−3 to n−6
fatty acids was only about half that in omnivores. In addition to the lower levels of n−3 fatty acids, the proportions of
palmitic and stearic acids were lower in serum cholesteryl esters, triglycerides and free fatty acids of vegans. The proportion
of oleic acid was slightly lower only in serum cholesteryl esters and erythrocyte phosphatidylserine. The results show that,
in the long term, the vegan diet has little effect on the proportions of oleic and arachidonic acids, whereas the levels of
n−3 fatty acids are depressed to very low levels with prolonged consumption of the high linoleic and oleic acid components
of this diet. 相似文献
11.
Rates of total and peroxisomal fatty acid oxidation were estimated from the production of14C-labeled CO2 and acid-soluble products from differently labeled [14C]fatty acids, in the absence and presence of antimycinrotenone, in homogenates of liver, heart and m. quadriceps. Total and
peroxisomal oxidation rates of palmitic, oleic and linoleic acid were 3–4 times higher than those of arachidonic and adrenic
acid which had higher oxidation rates than those of lignoceric and erucic acid. The peroxisomal contribution to the oxidation
of the last fatty acids was similar to or higher than that of palmitic acid. For all fatty acids tested in these tissues,
the mitochondrial contribution to β-oxidation was higher than the peroxisomal contribution.
Production of14CO2 and14C-labeled, acid-soluble metabolites from [13-14]arachidonic acid indicated that polyunsaturated fatty acids can be chain-shortened beyond their double bonds in m. quadriceps
and heart as well as in liver. Although 2,4-dienoyl-CoA reductase requires NADPH, addition of this coenzyme did not influence
arachidonic acid oxidation. Arachidonic acid oxidation was inhibited by palmitic acid in mitochondria and peroxisomes, but
arachidonic acid had only a slight effect on palmitic acid oxidation. 相似文献
12.
Triacylglycerol structure of human colostrum and mature milk 总被引:2,自引:0,他引:2
Jean-Charles Martin Philippe Bougnoux Jean-Michel Antoine Monique Lanson Charles Couet 《Lipids》1993,28(7):637-643
Because triacylglycerol (TAG) structure influences the metabolic fate of its component fatty acids, we have examined human
colostrum and mature milk TAG with particular attention to the location of the very long chain polyunsaturated fatty acid
on the glycerol backbone. The analysis was based on the formation of various diacylglycerol species from human milk TAG upon
chemical (Grignard degradation) or enzymatic degradation. The structure of the TAG was subsequently deduced from data obtained
by gas chromatographic analysis of the fatty acid methyl esters in the diacylglycerol subfractions. The highly specific TAG
structure observed was identical in mature milk and colostrum. The three major fatty acids (oleic, palmitic and linoleic acids)
each showed a specific preference for a particular position within milk TAG: oleic acid for thesn-1 position, palmitic acid for thesn-2 position and linoleic acid for thesn-3 position. Linoleic and α-linolenic acids exhibited the same pattern of distribution and they were both found primarily
in thesn-3 (50%) andsn-1 (30%) positions. Their longer chain analogs, arachidonic and docosahexaenoic acids, were located in thesn-2 andsn-3 positions. These results show that polyunsaturated fatty acids are distributed within the TAG molecule of human milk in
a highly specific fashion, and that in the first month of lactation the maturation of the mammary gland does not affect the
milk TAG structure. 相似文献
13.
Qamar Khalid Ahmed Saeed Mirza A. Hameed Khan 《Journal of the American Oil Chemists' Society》1968,45(4):247-249
The body oils of 13 species of marine edible fishes found around the Karachi-Makran coast were studied by gas-liquid chromatography
(GLC) for their fatty acid composition. The analyses showed the presence of fatty acids with chain lengths from 10 to 24 carbon
atoms and with zero to six double bonds. The oils were found to be rich in polyunsaturated acids, particularly the penta-
and hexaenoic. Certain major fatty acids were found to vary widely among the species: myristic acid 2.3 to 13.7%; palmitic
11.6 to 41.2%; stearich 7.2 to 23.2%; oleic 6.9 to 29.6%; eicosapentaenoic 1.4 to 19.0%; docosapentaenoic zero to 10.2%; and
docosahexaenoic zero to 36.4%. The linoleic and linolenic acids were present in small amounts in some of the fish oils, and
arachidonic acid was present in all of them. 相似文献
14.
Rapidly growing neonatal mammals accrete relatively large quantities of long chain (≥C20) polyunsaturated fatty acids (LCP) in membrane phospholipids. We have examined accumulation of ω6 LCP in suckling neonatal
rat pups during the first 14 d of life when their dams received essential fatty acids in the form of triglycerides containing
linoleic acid or arachidonic acid. Dietary levels of these fatty acids were either 1 or 5% of total dietary fatty acids. The
fatty acid profile of pup stomach contents (composed solely of the dams' milk) and plasma lipids, as well as liver and brain
phospholipids, were determined. Stomach linoleic and arachidonic acid levels reflected the diet of the dams. Pup plasma and
liver arachidonic acid levels increased progressively from the group receiving 1% linoleic acid to 5% linoleic acid and from
1% arachidonic acid to 5% arachidonic acid. Interestingly, brain phosphatidylethanolamine and phosphatidylcholine arachidonic
acid levels were more stable than plasma or liver levels. These results suggest that the brain may be capable of either selective
transport of ω6 LCP or chain elongation/desaturation of linoleic acid. These data indicate that care must be exercised when
adding LCP to infant formula since widely divergent accretion rates of arachidonic acid may occur in various tissues. 相似文献
15.
Composition and metabolism of fatty acids in phospholipids of density-separated red cells of rats 总被引:1,自引:0,他引:1
Fatty acid compositions of phosphatidylcholine (PC) and phosphatidylethanolamine (PE) and the rates of fatty acid esterification
to these phospholipids (PL) were measured in intact rat red cell populations of different ages separated by density gradient
centrifugation in order to clarify changes in membrane lipids of red blood cells during in vivo aging. Fatty acid compositions
of PC and PE altered progressively as red cells became denser. Changes in unsaturated fatty acids occurred predominantly at
the 2-position of PC and PE and those in saturated fatty acids at both positions. The esterification rates of 5 major fatty
acids decreased as red cells became denser and those of oleic acid, linoleic acid and arachidonic acid to both PC and PE of
fraction I cells (oldest cells) were 37–51% those of fraction IV cells (youngest cells). Reduction in the rates of fatty acid
esterification appeared to occur in the course of red cell maturation because reticulocyte-enriched cell fractions showed
4.5–14.5 times higher rates of linoleic acid and arachidonic acid esterifications to PC and PE. 相似文献
16.
Minimal deviation hepatoma cells were cultured in a modified Swim's 77 medium supplemented with decreasing amounts of serum,
lipid-free serum, and lipid-free serum containing added palmitic or linoleic acids. Cellular phospholipids were extracted
and the class distribution determined quantitatively. The fatty acid composition of each phospholipid class was determined,
and the percentages from cells grown on each of the various media were compared. Cellular phospholipid class and fatty acid
compositions differed from media compositions, indicating that intact serum phospholipids are not incorporated into cellular
structures. Phosphatidylcholine percentages decreased as the media serum and lipid levels decreased, while phosphatidylinositol
and phosphatidylethanolamine percentages increased. Sphingomyelin of cells grown in medium containing added linoleic acids
contained a high level of a 24∶2 acid. All classes, except sphingomyelin, contained elevated levels of 18∶1 acid and decreased
levels of polyunsaturated fatty acids, relative to normal rat liver. Cells cultured on lipid-free medium did not contain increased
concentrations of 20∶3 acid, suggesting that this hepatoma cell cannot desaturate monoenoic acids. Phosphoglycerides of cells,
grown on lipid-free medium, had the highest monoene fatty acid concentration, whereas those cells grown on media containing
added linoleic acid had the lowest concentrations, suggesting that linoleate may inhibit or regulate monoenoic acid biosynthesis
in this cell. These mass data also demonstrate that monoenoic fatty acid biosynthesis in this cultured hepatoma cell responds
to dietary changes. 相似文献
17.
Timo Paavola Ulrich Bergmann Sanna Kuusisto Sakari Kakko Markku J. Savolainen Tuire Salonurmi 《International journal of molecular sciences》2021,22(9)
HDL particles can be structurally modified in atherosclerotic disorders associated with low HDL cholesterol level (HDL-C). We studied whether the lipidome of the main phosphatidylcholine (PC), lysophosphatidylcholine (LPC) and sphingomyelin (SM) species of HDL2 and HDL3 subfractions is associated with premature coronary heart disease (CHD) or metabolic syndrome (MetS) in families where common low HDL-C predisposes to premature CHD. The lipidome was analyzed by LC-MS. Lysophosphatidylcholines were depleted of linoleic acid relative to more saturated and shorter-chained acids containing species in MetS compared with non-affected subjects: the ratio of palmitic to linoleic acid was elevated by more than 30%. A minor PC (16:0/16:1) was elevated (28–40%) in MetS. The contents of oleic acid containing PCs were elevated relative to linoleic acid containing PCs in MetS; the ratio of PC (16:0/18:1) to PC (16:0/18:2) was elevated by 11–16%. Certain PC and SM ratios, e.g., PC (18:0/20:3) to PC (16:0/18:2) and a minor SM 36:2 to an abundant SM 34:1, were higher (11–36%) in MetS and CHD. The fatty acid composition of certain LPCs and PCs displayed a characteristic pattern in MetS, enriched with palmitic, palmitoleic or oleic acids relative to linoleic acid. Certain PC and SM ratios related consistently to CHD and MetS. 相似文献
18.
Samples of radioactive bile were collected from rats after intravenous injection of potassium soaps ([9–103H2] or [114C] oleate, [114C] linoleate or [9–103H2] palmitate). These radioactive acids were chosen because it is well established that, in natural phosphatidyl cholines, palmitic
acid is located chiefly at the 1 position and linoleic and oleic acids at the 2 position. After incubation of bile with pancreatic
juice, the labeling of unchanged biliary phospholipids was higher when native bile was labeled with oleic acid than with palmitic
or linoleic acids. These data suggest that monounsaturated molecular species of biliary phospholipids are more resistant than
the diunsaturated ones to in vitro hydrolysis by phospholipase A2. Ninety min after introduction of the radioactive bile into the upper part of the rat duodenum, high labeling of luminal
phospholipids was observed regardless of the bile sample used, although labeling of free fatty acids was always low. The passage
of intact biliary phospholipids through the intestinal epithelium is discussed. 相似文献
19.
The oxidative stability of soybean oil triacylglycerols (TAG) obtained from genetically modified soybeans was determined before
and after chemical randomization. Soybean oil oxidative studies were carried out under static oxygen headspace at 60°C in
the dark and oxidative deterioration was monitored by peroxide value, monometric and oligomeric oxidation products, and volatile
compounds. Randomization of the soybean oil TAG improved the oxidative stability compared to the natural soybean oil TAG.
Oxidative stability was improved by three factors. Factor one was the genetic modification of the fatty acid composition in
which polyunsaturated acids (such as linolenic and linoleic acids) were decreased and in which monounsaturated fatty acids
(such as oleic) and saturated acids (palmitic and stearic) were increased. Factor two was the TAG compositional modification
with a decrease in linolenic and linoleic-containing TAG and an increase in TAG with stearic and palmitic acids in combination
with oleic acid. Factor three was the TAG structure modification accomplished by an increase in saturated fatty acids and
a decrease in linoleic and linolenic acids at the glycerol moiety carbon 2.
Presented at the AOCS Annual Meeting & Expo, Chicago, IL, May 10–13, 1998. 相似文献
20.
Deborah Pacetti Paolo Lucci Emanuele Boselli Natale G. Frega 《European Journal of Lipid Science and Technology》2009,111(12):1201-1211
The dietary supplementation with antioxidant‐enriched foods was evaluated for the phospholipid (PL) class and molecular species composition of human plasma. Twenty healthy subjects were supplied with α‐tocopherol (13.7 mg/day) and coenzyme Q10 (19.4 mg/day) by enriched milk, a dessert, fruit juice and yogurt for 21 days. Phosphatidylcholine (85.2%) and sphingomyelin (10.9%) were the main PL in all samples. Differences among the contents of PL classes were not found. However, principal component analysis showed differences in the PL molecular species 2 h after the mid‐morning snack. An increase of phosphatidylinositol (PI) containing stearic/arachidonic (on average from 42.5 to 47.0%), stearic/docosahexaenoic (3.2 vs. 4.9%), oleic/arachidonic and palmitic/docosapentaenoic acid (2.4 vs. 3.7%) was observed. The decreasing species of PI were palmitic/linoleic (5.7 vs. 4.3%), palmitic/oleic (8.1 vs. 6.9%) and stearic/linoleic acid (17.4 vs. 13.8%) after the mid‐morning snack. Phosphatidylethanolamine (PE) species showed an opposite trend with respect to PI: A decrease was registered for stearic/arachidonic (17.0 vs. 15.8%), stearic/docosahexaenoic (7.2 vs. 4.9%), oleic/arachidonic and palmitic/docosapentaenoic acid (5.8 vs. 4.8%); an increase was observed for the PE species containing oleic/linoleic (5.5 vs. 7.5% on average after the mid‐morning snack), stearic/linoleic (19.7 vs. 23.4%) and stearic/oleic acid (11.4 vs. 13.9%). 相似文献