Platelet activating factor metabolism

Gardner, C.R., Laskin, J.D., and Laskin, D.L., Platelet-activating factor-induced calcium mobilization and oxidative metabolism in hepatic macrophages and endothelial cells, J. Leukoc. Biol., 53, 190, 1993. 

Lamant V, Mauco G, Braquet P, Chap H, Douste-Blazy L. (1987). Inhibition of the metabolism of platelet activating factor (PAF-acether) by three specific antagonists from Ginkgo biloba. Biochem Pharmacol. 36(17) 2749-52. 

It is a cromolyn analogue. It is an antihistaminic (H antagonist) and probably inhibits airway inflammation induced by platelet activating factor (PAF) in primate. It is not a bronchodilator. It is used in asthma and symptomatic relief in atopic dermatitis, rhinitis, conjunctivitis and urticaria. It is absorbed orally and well tolerated. Bioavailability is 50% due to first pass metabolism and is primarily metabolized. The common side effects include dry mouth, sedation, dizziness and nausea. 

It has beat proposed that possible mechanisms underlying the neuroprotective and/or neurotrophic properties of EGb in the CNS indude influences on neurotransmitters, energy metabolism and membrane functions, as well as antioxidant activities and inhibition of platelet-activation factor (PAF). 

Shukla, S. D. and Hanahan, D. J. (1982) AGEPC (platelet activating factor) induced stimulation of rabbit platelets effects on phosphatidyl inositol, di- and tri- phos-phoinositides and phosphatidic acid metabolism, Biochem. Biophys. Res. Commun. 106, 697-703. 

Roth 01. (1986). Platelet arachidonic acid metabolism and platelet-activating factor. In Biodiemistry of Platelets (Phillips DR, and Shuman MA Eds.X PP. 69-100, Academic Press Inc. (London) Ltd., Londoa... 

Harmine was evaluated for its effects on both arachidonic acid metabolism and human platelet aggregation (platelet-activating factor) and found to be inactive [269]. 

Kono, N. et al. Protection against oxidative stress-induced hepatic injury by intracellular type II platelet-activating factor acetylhydrolase by metabolism of oxidized phospholipids in vivo. J. Biol. Chem. 283 (2008) 1628-36. 

FIGURE 25-3 Synthesis and degradation of platelet-activating factor. RCOO" is a mixture of fatty acids but is enriched in arachidonic acid that may be metabolized to eicosanoids. CoA, coenzyme A. 

Kusano, K., Seko, T., Tanaka. S., Shikaia, Y. Ando, T, Ida. S., Hosokawa, M.. Satoh, T. Yuzuriha, T.. and Horic, T. (1996). Purification and characterizaiion of monkey liver amidohydro-lascs and its relationship to a metabolic polymorphism of E6123, a platelet activating factor receptor antagonist. Drug Metab. Dittos., in press. 

Kusano K, Seko T, Tanaka S, et al. (1996). Purfication and characterization of Rhesus monkey liver amido hydrolases and their roles in the metabolic polymorphism for E6123, a platelet-activating factor receptor antagonist. Drug Metabol. Dispos. 24 1186-1191. 

Saeed, S.A., R.U. Simjee, G. Shamim, and A.H. GUani. 1995. Eugenol A dual inhibitor of platelet activating factor and ara-chidonic acid metabolism. Phytomedicine 2 23-28. 

Cerebral insufficiency refers to describe the people with age-related decline in mental function and decrease blood flow to the brain cause by clogged arteries. Platelet activating factor (PAF) is an inflammatory mediator, plays an important role in allergy, inflammatory processes, coronary, and cerebral vasoconstriction [178]. The production and release of PAF in the brain under various pathological conditions, including oxidant stress-induced ischemic injury [179]. The efficiency of EGb-761 on cerebral circulation and metabolism has been demonstrated in various models of cerebrovascular insufficiency and showed beneficial effect like cerebral edema in rats intoxicated with triethyltin chloride (TET) [180]. Moreover, oral or intravenous administrations EGb decrease cerebral edema development in gerbils [181]. In an animal study [182], EGb-761 and an extract of local ginkgo... 

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