Arachidonic acid occurrence

Nakane, S., Oka, S., Arai, S., Waku, K., Ishima, Y., Tokumura, A., and Sugiura, T. (2002). 2-Arachidonoyl-sn-glycero-3-phosphate, an arachidonic acid-containing lysophosphatidic acid Occurrence and rapid enzymatic conversion to 2-arachidonoyl-sn-glycerol, a cannabinoid receptor ligand, in rat brain. Arch. Biochem. Biophys. 402, 51-58. 

Specific differences to note are a 10-fold lower level of histamine in the mucosal mast cell and the occurrence of distinct proteases and proteoglycans and (possibly) a different arachidonic acid metabolism for each type (55). These differences are sufficiently great to conclude that extrapolation of data on PMC (on which most research has been carried out) to MMC would be unwise. 

Anandamide (arachidonoylethanolamide) is just one of a family of lipids known as W-acylethanolamines (NAEs), which are generated from membrane phospholipids via a common enzymatic pathway (see below). The occurrence of anandamide in an organism is dependent on (1) the presence of the fatty acid arachidonic acid as a component of membrane phospholipids and (2) the presence of enzymes that can catalyse formation of NAEs from membrane phospholipids. Therefore, the phylogenetic distribution of anandamide is likely to reflect a combination of both the phylogenetic distribution of arachidonic acid as a fatty acid component of membrane lipids and the phylogenetic distribution of the enzymes that can catalyse formation of NAEs. 

Nakamura, T., P.M. Henson, and R.C. Murphy Occurrence of oxidized metabolites of arachidonic acid esterified to phospholipids in murine lung tissue. Anal. Biochem. 262 (1998) 23-32. 

Jett, M., Brinkley, W., Neill, R., Gemski, R, and Hunt, R. (1990) Staphylococcus aureus enterotoxin B challenge of monkeys correlation of plasma levels of arachidonic acid cascade products with occurrence of illness. Infect. Inwmn. 58 3494—3499. 

Physiological Function of n-6 DPA Reported to Date. Not only is the occurrence of n-6 DPA rare in the biosphere it is also a minor fatty acid in mammals. Of the n-6 essential fatty acids (EFA) for primates or humans, linoleic acid (LA, 18 2n-6) and arachidonic acid (AA, 20 4n-6) are the most prominent and important. Among the docosapolyenoic acids (22-carbon chain), which can cross the blood-brain barrier more than the eicosapolyenoic acids (20-carbon), DHA (an n-3 EFA) is the most important. In mammals, the levels of n-6 DPA in brain and retina increase in accordance with n-3 essential fatty acid deficiency (EFAD). Is the increase only compensatory for DHA or does n-6 DPA have any positive physiologic functions ... 

The occurrence of 5-lipoxygenase was implicated from the isolation of 5-hydroxy-6,8,11,14-eicosatetraenoic acid produced from arachidonic add by rabbit polymorphonuclear leukocytes [194]. The enzyme is now known to initiate the biosynthetic pathway of some leukotrienes, and is considered to occur in various leukotriene-synthesizing tissues rabbit peritoneal polymorphonuclear leukocytes [194], murine mastocytoma cells [201], human polymorphonuclear leukocytes [202], rat peritoneal mononuclear cells [203,204], rat basophilic leukemia cells [205,206], and horse eosinophils [207]. The 10000 X g supernatant of rat basophilic leukemia cells produces 5-hydroxy arachidonic acid, and the reaction requires the presence of caldum ion and glutathione [206]. The 100000 X g supernatant of guinea pig peritoneal polymorphonuclear leukocytes contains a 5-lipoxygenase, which also requires calcium ion and produces 5-hydroperoxy acid in the absence of glutathione [199]. 

Long-chain fatty acids. Small amounts of 20 0, 22 0 and 24 0 have been recorded in a few yeasts but are probably present as trace continuents in many species. Polyunsaturated, long-chain fatty adds have usually been only recorded in a few instances Cottrell (1989) produced evidence for the occurrence of di-homo-y-linolenic acid (20 3) and arachidonic acid (20 4) in the yeast Dipodascopsis uninucleata (Botha et al., 1992). However, in a detailed examination of a number of related yeasts, Botha et al. (1992) did not find the presence of even traces of 20 4 in any of nearly 50 species and strains that were examined. 

Nakamura, H., J. Kobayashi, Y. Ohizumi, and Y. Hirata The Occurrence of Arachidonic Acid in the Venom Duct of the Marine Snail Conus textile. Experientia 38, 897 (1982). 

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