Effects of a trans isomer of arachidonic acid on rat platelet aggregation and eicosanoid production.
The addition of a trans isomer of arachidonic acid (20:4 delta 14trans) to rat platelet suspensions inhibited the aggregation induced by 7.5 microM of arachidonic acid. This inhibitory effect of 20:4 delta 14trans was significant at concentrations of 7.5-22.5 microM and the range of inhibition was 20% at an inhibitor/substrate ratio (I/S) 1 to 66% when I/S reached 3. However, the addition of its structural homolog (20:3n-9) or the natural isomer (20:4n-6) did not induce any modification of the platelet aggregation. In parallel, adding 20:4 delta 14trans to the platelet significantly decreased thromboxane B2 and 12-hydroxyheptadecatrienoic acid production. In contrast, the 12-lipoxygenase pathway was stimulated, as 12-hydroxyeicosatetraenoic acid production increased up to 55% when the I/S reached 3. 20:3n-9, not being a substrate of the cyclooxygenase, did not induce any significant modification in the formation of thromboxane B2 and 12-hydroxyheptadecatrienoic acid. 20:4 delta 14t alone did not induce any platelet aggregation. However, this fatty acid was metabolized to a limited extent into two products that have still to be identified. One of them would be a product of the 12-lipoxygenase pathway.
Berdeaux
O
O
INRA, Unité de Nutrition Lipidique, Dijon, France.
Chardigny
J M
JM
Sébédio
J L
JL
Mairot
T
T
Poullain
D
D
Vatèle
J M
JM
Noël
J P
JP
D019377:12-Hydroxy-5,8,10,14-eicosatetraenoic Acid / Q000096:biosynthesis; D000818:Animals; D001092:Arachidonate 12-Lipoxygenase / Q000378:metabolism; D016718:Arachidonic Acid / Q000494:pharmacology*; D015777:Eicosanoids / Q000096:biosynthesis*; D005231:Fatty Acids, Unsaturated / Q000096:biosynthesis; D015289:Leukotrienes / Q000378:metabolism; D008297:Male; D010974:Platelet Aggregation / Q000187:drug effects*; D010975:Platelet Aggregation Inhibitors / Q000494:pharmacology; D051381:Rats; D017208:Rats, Wistar; D013237:Stereoisomerism; D013929:Thromboxane B2 / Q000096:biosynthesis
D015777:Eicosanoids; D005231:Fatty Acids, Unsaturated; D015289:Leukotrienes; D010975:Platelet Aggregation Inhibitors; D016718:Arachidonic Acid; C008033:12-hydroxy-5,8,10-heptadecatrienoic acid; D013929:Thromboxane B2; D019377:12-Hydroxy-5,8,10,14-eicosatetraenoic Acid; C021201:12-HPETE; D001092:Arachidonate 12-Lipoxygenase