Arachidonic acid(ARA) yog ib qho tseem ceeb fatty acid nyob rau hauv tib neeg lub cev, thiab nws kuj yog ib tug ntau tshaj thiab dav faib polyunsaturated fatty acid nyob rau hauv tib neeg lub cev. Nws yog ib qho tseem ceeb rau kev tswj cov qauv thiab kev ua haujlwm ntawm cov cell membranes hauv vivo. ARA muaj dav nyob rau hauv cov ntaub so ntswg tsiaj, suav txog li 1 feem pua ntawm cov ntshav phospholipids, heparin thiab cephalin, li 15 feem pua rau 40 feem pua ntawm adrenal phospholipid fatty acids, thiab txawm tias siab li 70 feem pua ntawm cov paj hlwb.
ARA yog ib qho tseem ceeb fatty acid. Hauv vivo, ARA tuaj yeem tsim los ntawm desaturation thiab carbon saw txuas ntxiv ntawm linoleic acid. Kev tswj hwm kev ua haujlwm lom neeg ntawm linoleic acid yog ua tiav los ntawm cov metabolites ntawm ARA. ARA kuj muaj cov haujlwm xws li tswj hwm lub plawv excitability, koom nrog hauv neuroendocrine, txhawb kev faib cell, thiab inhibiting platelet aggregation.
ARA txhawb kev kho thiab kev loj hlob ntawm cov leeg pob txha los ntawm kev hloov mus rau prostaglandin PGF thaum lub sij hawm thiab tom qab kev tawm dag zog lub cev. Nws tsis tsuas yog tshwm sim raws li ib qho tseem ceeb heev lipid nyob rau hauv cov ntaub so ntswg mammalian (tshwj xeeb tshaj yog cov paj hlwb), tab sis kuj yog ib qho tseem ceeb precursor rau lub synthesis ntawm prostaglandins nyob rau hauv tib neeg, nrog rau ntau yam kev ua ub no lom neeg thiab cov khoom noj muaj txiaj ntsig tseem ceeb.
Metabolic pathways ntawm ARA
Raws li cov precursors ntawm ntau yam lom lom tshuaj lom neeg, muaj peb lub ntsiab enzymes koom nrog hauv ARA metabolism. Lub ntsiab oxidation tshwm sim uas catalyze cov metabolism ntawm ARA yog: epoxidation, allylic oxidation thiab Omega-hydroxylation. Raws li ib txwm muaj lub cev muaj zog, qib ntawm ARA dawb yog tsawg heev. Thaum lub cell membrane raug rau ntau yam stimuli (xws li mob), ARA raug tso tawm los ntawm lub pas dej ua ke phospholipid, tsim ib tug loj npaum li cas ntawm arachidonic acid, uas yog hloov dua siab tshiab rau hauv biologically active metabolites. Hauv ntau lub hlwb, ARA raug tso tawm los ntawm lub cell endoplasmic reticulum thiab lub hnab ntawv nuclear thiab tom qab ntawd thauj mus los ntawm cov hlwb los tsim cov khoom siv roj ntsha 2-carbon derivatives.