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Biomedical subjects

K Satouchi

Publications and source records attributed to K Satouchi.

54 records · Page 3Linked to original sources
PubMed1985

Production of platelet-activating factor by washed rabbit platelets.

Production of platelet-activating factor by washed rabbit platelets under stimulation with the ionophore A23187 was investigated utilizing two groups of platelet preparations. The first platelet preparation contained 0.03 +/- 0.02% contaminating white cells, while the second preparation contained 0.48 +/- 0.27% white cells. The latter preparation produced platelet-activating factor, mainly 1-hexadecyl-2-acetyl-sn-glycero-3-phosphocholine, 8.3 +/- 6.3 pmol (mean +/- standard deviation) with a range of 2.6 to 21.4 pmol (n = 9), followed by small quantities of 1-octadecenyl- and 1-octadecyl-2-acetyl-sn-glycero-3-phosphocholine. In contrast, there was no production of 1-alkyl-2-acetyl-sn-glycero-3-phosphocholine by the former platelet preparation having 0.03% leukocytes. These quantitative analyses were carried out by the selected ion monitoring technique and it was concluded that it is necessary to consider the presence of contaminating white cells in studies on the production of platelet-activating factor by platelets.

Animals↗
PubMed1984

Metabolism of 1-O-alkyl-2-acetyl-sn-glycerol by washed rabbit platelets: formation of platelet activating factor.

A new type of neutral lipid, 1-O-alkyl-2-acetyl-sn-glycerol (AAG), induced a delayed aggregation pattern on interaction with washed rabbit platelets. Although far less potent on a molar basis than platelet activating factor (1-O-alkyl-2-acetyl-sn-glycero-3-phosphocholine, AGEPC, nevertheless this compound caused an aggregation, albeit delayed in time, remarkably similar to that exhibited by AGEPC. In view of the possible formation of AGEPC in this reaction, AAG was incubated with washed rabbit platelets, and a lipid corresponding in chromatographic behavior to AGEPC was isolated and identified as such by a combined gas-liquid chromatography/mass spectrometry technique coupled with selected ion monitoring.

Animals↗
PubMed1984

Molecular species of phospholipid in rat hepatomas and in fetal, regenerating, and adult rat livers.

The molecular species of phospholipid in rat hepatomas were found to be different from those in normal adult liver. Phosphatidylcholine in Yoshida hepatoma contained phosphatidylcholine with 34:1 as the sums of the chain length and of the unsaturation of fatty acids esterified at C-1 and C-2 of glycerol, as an example (PC34:1), PC36:2, PC36:1, PC34:2, and PC36:3, and its phosphatidylethanolamine contained PE36:2, PE36:1, PE38:4, PE36:3, and PE34:1 as major species, whereas phosphatidylcholine in normal adult liver contained PC38:4, PC36:2, PC34:2, PC36:4, and PC34:1, and its phosphatidylethanolamine (PE) contained PE38:4, PE38:6, PE40:6, PE36:4, and PE36:2, with their level decreasing in that order. While Morris hepatoma also had significantly lower amounts of species containing polyunsaturated fatty acids, there were higher levels of those phosphoglycerides containing monoenoic and dienoic fatty acids. Regenerating liver showed similar patterns of molecular species of both phospholipids to those of normal liver. In contrast, fetal liver had similar molecular species of phosphatidycholine to those of hepatomas, but had similar species of phosphatidylethanolamine to those of normal and regenerating livers.

Animals↗
PubMed1983

Application of selected ion monitoring to determination of platelet-activating factor.

The selected ion monitoring (SIM) technique was applied to determination of platelet-activating factor (PAF) or acetyl glyceryl ether phosphorylcholine (AGEPC). Two types of PAF, 1-hexadecyl- and 1-octadecyl-2-acetyl-sn-glyceryl-3-phosphorylcholine (C16 = 0 AGEPC and C18 = 0 AGEPC), were found in human neutrophils on the challenge with ionophore A23187. The contents of C16 = 0 AGEPC in 1 X 10(7) neutrophil cells of four volunteers, respectively, were 47, 18, 59, and 73 ng and those of C18 = 0 AGEPC were 22, 4, 19, and 31 ng.

Adult↗
PubMed1982

Vasoactive properties of acetyl glyceryl ether phosphorylcholine and analogues.

Intradermal injection of 0.1 pmole (52 pg.) of acetyl glyceryl ether phosphorylcholine (AGEPC) in guinea pigs induced increased vascular permeability as assessed by a skin-blueing model. Rabbits and rats showed increased vascular permeability with 1.0 pmole (520 pg.) of AGEPC. On a molar basis, from 1,000 to 10,000 times more histamine was required to induce skin blueing in the same animals. In rabbits and guinea pigs, the increased vascular permeability induced by AGEPC occurred as an early, transient phase and as a delayed, prolonged phase. The early, transient phase was not inhibited by chlorpheniramine doses which markedly reduced or abrogated histamine-induced blueing. AGEPC was 100 to 1000 times more potent than histamine on a molar basis for the induction of vasoconstriction in a blued skin assay in guinea pigs. These studies demonstrate that AGEPC has potent vasoactive properties and provide additional information that implicates this acetylated alkyl phosphoglyceride as a mediator of the acute inflammatory process.

Animals↗
PubMed1981

Modification of the polar head group of acetyl glyceryl ether phosphorylcholine and subsequent effects upon platelet activation.

A series of phosphoglycerides containing the same structural unit, 1-O-alkyl-2-acetyl-sn-glycerol, was prepared with the following polar head groups: -3-phosphoric acid (AGEPA), -3-phosphorylethanol (AGEPEt), -3-phosphorylethanolamine (AGEPE), -3-phosphoryl-N-monomethylethanolamine (AGEPMME), -3-phosphoryl-N,N-dimethylethanolamine (AGEPDME), and -3-phosphorylcholine (AGEPC). These compounds were synthesized primarily by phospholipase D modification of AGEPC. The characterization of these derivatives was achieved through thin layer chromatography, infrared spectrometry, gas-liquid chromatography, and combined gas-liquid chromatograph-mass spectrometry. Their ability to induce irreversible aggregation and 50% secretion of serotonin from washed rabbit platelets was investigated. The latter secretory activity, expressed on a molar basis (60 s following platelet stimulation) was shown to be particularly sensitive to the nature of the polar head group as follows: AGEPA, 8.3 X 10(-7) M; AGEPE, 6.8 X 10(-7) M; AGEPEt, 4.0 x 10(-7) M; AGEPMME, 3.7 X 10(-9) M; AGEPDME, 4.5 X 10(-10) M; and AGEPC, 1.8 X 10(-10) M. It was concluded that the polar head group of the various acetyl glyceryl ether phosphoglycerides had an important role in expressing the biological activity of this unique type of phosphoglyceride towards platelets. It appears likely that the polar head group of the various acetyl glyceryl ether phosphoglycerides had an important role in expressing the biological activity of this unique type of phosphoglyceride towards platelets. It appears likely that the recognition site (receptor site) on platelets is more reactive to the dimethylethanolamine or teh quaternary ammonium base, choline, than to any of the other polar head groups under consideration.

Animals↗
PubMed1980

Changes in molecular species of rat liver choline glycerophospholipids with development.

Molecular species of rat liver choline glycerophospholipids were investigated at various stages of development by a gas chromatograph-mass spectrometer system. They were composed mainly by 1,2-diacyglycerophosphocholine and changed with development particularly during the perinatal period.. In the prenatal period, the major species were '32 : 0' (mainly 16 : 0/16 : 0, dipalmitoyl species), '34 : 0' (mainly 16 : 0/18 : 0, palmitoystearoyl speciesY, '34 : 1' (mainly 16 : 0/18 : 1, palmitoyloleoyl species) and '34 : 2' (mainly 16 : 0/18 : 2, palmitoyllinoleoyl speciesY and '32 : 0' decreased rapidly and '34 : 1' increased as the stage proceeded. After birth, however, polyunsaturated species such as '34 : 4' and '38 : 4-6' increased rapidly in contrast to the decrease of '32 : 1, 34 : 1, 36 : 1, and 34 : 0'. Moderate changes were observed in these species during subsequent development.

Animals↗
PubMed1979

Studies on molecular species of choline glycerophospholipids of developing rat brain.

The chronological changes in molecular species of choline glycerophospholipids were studied for cerebra of 17-, 19- and 21-day-old rat fetuses, and 3-, 6-, 12-, 24- and 90-day-old rats. The molecular species found by gas chromatography-mass spectrometry and selected ion retrieval technique were phosphatidylcholines of '30 : 0, 32 : 0, 32 : 1, 34 : 0, 34 : 1, 34 : 2, 36 : 0, 36 : 1, 36 : 2, 36 : 3, and 36 : 4' where the larger number indicates the sum of chain lengths on positions C-1 and C-2; the smaller number is the total number of double bonds. Of these molecular species, '32 : 0' (mainly 16 : 0/16 : 0, dipalmitoyl glycerophosphorylcholine), '34 : 1' (mainly 16 : 0/18 : 1, palmitoyloleoyl glycerophosphorylcholine), '34 : 0' (16 : 0/18 : 0, palmitoylstearoyl glycerophosphorylcholine), '32 : 1' (mainly 16 : 0/16 : 1, palmitoylpalmitoleoyl glycerophosphorylcholine and '30 : 0' (14 : 0/16 : 0, myristoylpalmitoyl glycerophosphorylcholine) were main species. The '32 : 0' species increased to about 44% at around the 10th day and thereafter remained nearly constant. '34 : 1' and '34 : 0' decreased to about 17 and 6% at that time and then increased to about 30 and 14%, respectively. '30 : 0' increased from last stage of gestation to the 6th day and then decreased. '32 : 1' was about 16% for 17-day-old fetus and decreased grandually. '36 : 1' (18 : 0/18 : 1, stearoyloleoyl glycerophosphorylcholine) increased at the latter part of development.

Aging↗
PubMed1979

Separation and determination of oleic and cis-vaccenic acids by gas-liquid chromatography mass spectrometry using a polar cyanopropylsiloxane liquid phase.

The separation and quantification of the monoenoic isomeric oleic (cis-9-octadecenoic) and cis-vaccenic (cis-11-octadecenoic) acids as their pyrrolidine derivatives, was studied with a gas chromatograph mass spectrometer system using mass chromatography. By monitoring the characteristic ions of the pyrrolidine derivatives of oleic (m/z 208 and 222) and cis-vaccenic (m/z 210 and 224) acids, both derivatives were separated. The ratio of m/z 210 to 208 was proportional to the relative amounts of cis-vaccenic to oleic acid. By this method, the content of cis-vaccenic acid in choline phosphoglycerides from rat liver and Yoshida ascites hepatoma (AH 7974) was determined.

Animals↗
PubMed1979

Use of t-butyldimethylchlorosilane/imidazole reagent for identification of molecular species of phospholipids by gas-liquid chromatography mass spectrometry.

The t-butyldimethylsilyl derivatives of 1,2-diakyl, 1-alk-1'-enyl-2-acyl, 1-alkyl-2-acyl and 1,2-diacyl glycerols were analysed with a gas chromatograph mass spectrometer system. The characteristic fragment ions were as follows. The molecular weight determining ion was [M-57]+, which was formed by cleavage of the t-butyl radical from the molecular ion. The nature of the alk-1'-enyl residue could be determined by the presence of ions at [RCH-CH 56]+ and [RCH = CH + 130]+ (RCH = CH = alk-1'-enyl), and the alkyl residue by the ion at [R + 130]+(R = alkyl group). Ions giving information about the acyl group, [RCO]+, [RCO + 74]+ and [M-RCH = CHO, -RO or -RCOO]+ were also observed. The mass spectra of pairs of trimethylsilyl and t-butyldimethylsilyl derivatives showed differences in several respects. The t-butyldimethylsilyl derivatives gave more effective information for elucidating the structure of phosphoglycerides.

Diglycerides↗
PubMed1978

Studies on trimethylsilyl derivatives of 1,2-dialkylglycerols by gas-liquid chromatography mass spectrometry.

Trimethylsilyl derivatives of 1,2-dihexadecyl- and 1,2-dioctadecyl-glycerols were subjected to analysis by a gas chromatograph mass spectrometer system. The mass chromatographic identification of four kinds of glycerophospholipids, 1,2-dihexadecyl, 1-hexadec-1-enyl-2-hexadecanoyl, 1-hexadecyl-2-hexadecanoyl- and 1,2-dihexadecanoyl-glycerol is also described.

Chromatography, Gas↗
PubMed1977

Studies on trimethylsilyl derivatives of 1-alk-1enyl-2-acyl glycerols by gas-liquid chromatography mass spectrometry.

Trimethylsilyl derivatives of 1-hexadec-1-enyl-2-decanoyl and -2-octadecenoylglycerols and 1-octadec-1-enyl-2-decanoyl and -2-octadecenoylglycerols were subjected to analysis by a gas chromatograph mass spectrometer system. The characteristic ions are as follows: (1) ions at [M-15]+ and [M-90]+- are observed, 2 or 16 mass units less than those of the corresponding 1-alkyl-2-acyl or 1,2-diacyl derivatives; (2) the base peak is m/e 129; (3) the ion at [M-R1CH=CHO]+ or [R2COO+130]+ is present in high abundance; (4) ions at m/e 311 and 339, characteristic of trimethylsilyl derivatives of 1-hexadec-1-enyl and 1-octadec-1-enylglycerols, are due to [R1CH-CHO-1)+73]+, also confirmed from studies on the perdeuteriotrimethylsilyl derivatives; (5) several ions based on one acyl group, [R2CO]+, [R2CO+74]+ and [R2COO+74]+ are also observed.

Acylation↗
PubMed1977

Studies of molecular species of fetal lung lecithins by gas-liquid chromatography mass spectrometry.

The molecular species of lung lecithins obtained from rabbit and rat fetuses at different days of gestation and from newborns were analysed as TMS derivatives of the corresponding diglycerides in a gas chromatograph mass spectrometer system by selected ion retrieval. In the latter part of gestation, the order of the main molecular species of lung lecithins, PCn, was PC32 greater than PC34 greater than PC30, while at an earlier stage it was PC34 greater than PC32 greater than PC30. During gestation the change of PC32:0, dipalmitoyllecithin, was remarkable. Ether lecithins are also discussed.

Animals↗
PubMed1976

Studies on trimethylsilyl derivatives of 1-alkyl-2-acylglycerols by gas-liquid chromatography mass spectrometry.

Trimethylsilyl derivatives of 1-hexadecyl-2-decanoyl-, -hexadecanoyl- and -octadecenoyglycerols and 1-octadecyl-2-decanoyl-, hexadecanoyl- and -octadecenoylglycerols as well as 1,2-dihexadecanoylglycerol were analysed by a gas chromatography mass spectrometer system. The following points are characteristic of the fragmentation pattern of these 1-alkyl-2-acyl derivatives: (1) in the spectra of alkyl acyl derivatives, ions at [M -15]+ and [M - 90A1+. are 14 mass units less than those of the corresponding diacyl derivatives; (2) the base peak is m/e 130; (3) alkyl acyl derivatives show fragments due to one acyl group instead of the two acyl groups of diacyl derivatives; (4) ions at m/e 314 and 342, [R1O + 73]+., are characteristic of the trimethylsilyl derivatives of hexadecyl- and octadecylglycerols, respecitvely; (5) the ion [M -R1O]+ is present, but the complementary alkoxy ion is absent.

Chromatography, Gas↗