Your browser doesn't support javascript.
loading
Mostrar: 20 | 50 | 100
Resultados 1 - 3 de 3
Filtrar
Mais filtros










Base de dados
Intervalo de ano de publicação
1.
Biochim Biophys Acta ; 1047(1): 29-34, 1990 Oct 22.
Artigo em Inglês | MEDLINE | ID: mdl-2174263

RESUMO

The present study was carried out to define more precisely how dietary (n-3) fatty acids mediate leukotriene and phospholipid metabolism in neutrophils. Neutrophils from chow-fed rats did not synthesize detectable levels of LTB5 or 5-hydroxyeicosapentanenoic acid. The ratio of esterified 20:4(n-6)/20:5(n-3) in the phospholipids of neutrophils from rats fed a corn oil/fish oil diet was 4.6. The ratio of LTB4/LTB5 made by these cells was 2.6, thus suggesting that 20:5(n-3) release and/or subsequent metabolism was somewhat more efficient than for 20:4(n-6). When tritiated lyso-platelet activating factor was added to neutrophils from chow-fed rats, it was deactivated primarily by acylation with arachidonic acid. With the fish oil-fed animals both arachidonic acid and 20:5(n-3) were transferred to deactivate lyso-platelet activating factor. Molecular species analysis of the resulting radioactive 1-O-alkyl-2-acyl-sn-glycerol-3-phosphocholine showed that 20:5(n-3) pairs with the same 1-O-alkyl groups and in approximately the same ratio as does arachidonate. Collectively, these studies show that once 20:5(n-3) is incorporated into neutrophil lipids it is metabolized in a similar way as is arachidonate.


Assuntos
Gorduras Insaturadas na Dieta/farmacologia , Ácidos Graxos/metabolismo , Óleos de Peixe/farmacologia , Neutrófilos/metabolismo , Acilação , Animais , Ácido Araquidônico , Ácidos Araquidônicos/metabolismo , Cromatografia Líquida de Alta Pressão , Gorduras Insaturadas na Dieta/administração & dosagem , Ácido Eicosapentaenoico/análogos & derivados , Ácido Eicosapentaenoico/metabolismo , Óleos de Peixe/administração & dosagem , Ácidos Hidroxieicosatetraenoicos/metabolismo , Leucotrieno B4/metabolismo , Masculino , Neutrófilos/efeitos dos fármacos , Fosfolipídeos/metabolismo , Fator de Ativação de Plaquetas/análogos & derivados , Fator de Ativação de Plaquetas/metabolismo , Ratos , Ratos Endogâmicos
2.
Lipids ; 24(6): 477-81, 1989 Jun.
Artigo em Inglês | MEDLINE | ID: mdl-2505009

RESUMO

When rats were fed a diet containing chow or fish oil for six weeks, the platelet phospholipid content and percent distribution were similar. In the fish oil fed animals there was a 54, 40, 41, and 24% reduction, respectively, in the levels of 20:4(n-6) in the choline-, ethanolamine-, inositol- and serine-containing glycerophospholipids. Dietary fish oil increased the total (n-3) polyunsaturated fatty acid content in all lipids. This effect was most pronounced in the ethanolamine glycerophospholipids which now contained 26, 11, and 4 nmols of 20:5(n-3), 22:5(n-3), and 22:6(n-3) in 10(9) cells. Ionophore A23187 stimulation of platelets from the chow fed rats resulted in the synthesis of 7, 64, and 3.5 nmols of 12-hydroxy-5,8,10-heptadecatrienoic acid, 12-hydroxy-5,8,10,14-eicosatetraenoic acid and 12-hydroxy-5,8,10,14,17-eicosapentaenoic acid, respectively, from 1 X 10(9) cells. The values from animals fed fish oil were 4, 18, and 27 nmol/10(9) platelets. It was not possible to detect any lipoxygenase products from 22:5(n-3) or 22:6(n-3), even though both acids are readily metabolized by lipoxygenase when added directly to platelets. These findings suggest that 22-carbon (n-3) fatty acids are not liberated when phospholipases are activated by calcium mobilization.


Assuntos
Plaquetas/metabolismo , Ácidos Eicosanoicos/biossíntese , Ácidos Graxos/sangue , Óleos de Peixe/administração & dosagem , Fosfolipídeos/sangue , Animais , Plaquetas/efeitos dos fármacos , Calcimicina/farmacologia , Cromatografia Líquida de Alta Pressão , Dieta , Ácidos Eicosanoicos/sangue , Masculino , Ratos , Ratos Endogâmicos
3.
J Lipid Res ; 30(1): 77-87, 1989 Jan.
Artigo em Inglês | MEDLINE | ID: mdl-2918252

RESUMO

When rats were fed a corn oil versus a corn oil-fish oil diet the overall phospholipid content and composition as well as the subclass distribution of the choline- and ethanolamine-containing glycerophospholipids from neutrophils were not altered. The serine-containing glycerophospholipids were characterized by high levels of stearic and oleic acids. When fish oil was added to the diet it replaced some of the arachidonate in both the inositol- and the serine-containing glycerophospholipids. In the corn oil-fed animals, 25.2 and 33.6 mole %, respectively, of the molecular species of 1,2-diacyl- and 1-O-alkyl-2-acyl-sn-glycero-3-phosphocholine contained arachidonate. The values for 1,2-diacyl and 1-O-alk-1'-enyl-2-acyl-sn-glycero-3-phosphoethanolamine were, respectively, 41 and 55.8 mole %. When half of the 5% corn oil in the diet was replaced by fish oil, there was a 53, 38, 27, and 25% reduction, respectively, in the level of arachidonate in these four lipid subclasses. The amount of 5,8,11,14,17-eicosapentaenoic acid incorporated into these four subclasses was always less than the decline in arachidonic acid. This was due, in part, to the acylation of small amounts of 22-carbon (n-3) acids into these lipids. Molecular species analysis demonstrated that 5,8,11,14,17-eicosapentaenoic acid paired with the same components at the sn-1 position, and in the same ratio, as did arachidonic acid. The amounts of 16- and 18-carbon saturated and unsaturated fatty acid at the sn-2 position were not altered by dietary change. Collectively, these findings suggest that 5,8,11,14,17-eicosapentaenoic and arachidonic acids are metabolized in a similar way by neutrophils. These studies also support the concept that neutrophils contain two metabolic pools of phospholipids. One pool is altered by dietary fat change while the pool containing 16- and 18-carbon acids is resistant to change when fish oil is included in the diet.


Assuntos
Colina/sangue , Gorduras Insaturadas na Dieta/farmacologia , Etanolaminas/sangue , Óleos de Peixe/farmacologia , Lipídeos/sangue , Neutrófilos/análise , Ácidos Fosfatídicos/sangue , Animais , Etanolamina , Masculino , Ratos , Ratos Endogâmicos
SELEÇÃO DE REFERÊNCIAS
DETALHE DA PESQUISA
...