arachidonic acid

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arachidonic acid

chemical compound

Also known as: 5,8,11,14-eicosatetraenoic acid

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June 18, 2026

Quick Summary

Arachidonic acid is a liquid unsaturated fatty acid with the chemical formula C₂₀H₃₂O₂. It is found in most animal fats and is essential for animal nutrition. This compound is a precursor to prostaglandins, which are lipid compounds that act as chemical messengers in humans and animals, regulating physiological processes and mediating inflammatory and immune responses.12

Prostaglandins are synthesized from unsaturated fatty acids, including arachidonic acid, which is a component of cell membranes. When cells are stimulated, arachidonic acid is released and can be converted into various compounds, including prostaglandins, thromboxanes, and leukotrienes, depending on the enzymes present. These compounds have diverse and potent biological activities, affecting processes such as blood pressure, blood clotting, inflammation, and smooth muscle contraction.2

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carboxylic acid
Unsaturated aliphatic acids
Arachidonic acid is important because the human body uses it as a starting material in the synthesis of two kinds of essential substances, the prostaglandins and the leukotrienes, both of which are also unsaturated carboxylic acids. Examples are PGE₂ (a prostaglandin) and LTB₄ (a leukotriene).…
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Arachidonic acid is important because the human body uses it as a starting material in the synthesis of two kinds of essential substances, the prostaglandins and the leukotrienes, both of which are also unsaturated carboxylic acids. Examples are PGE₂ (a prostaglandin) and LTB₄ (a leukotriene).…
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drug
Drugs that affect smooth muscle
…acids, the most important being arachidonic acid. These substances are important especially in producing tissue responses to injury. Among their most important sites of action are bronchial and uterine smooth muscle. Leukotrienes, for example, are powerful bronchoconstrictors, and they are believed to be synthesized and released during asthmatic attacks. Some…
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…acids, the most important being arachidonic acid. These substances are important especially in producing tissue responses to injury. Among their most important sites of action are bronchial and uterine smooth muscle. Leukotrienes, for example, are powerful bronchoconstrictors, and they are believed to be synthesized and released during asthmatic attacks. Some…
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prostaglandin
Synthesis of prostaglandins
…straight-chain, polyunsaturated fatty acid precursor arachidonic acid.
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…straight-chain, polyunsaturated fatty acid precursor arachidonic acid.
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fat
Functions in plants and animals
…are hormonelike compounds derived from arachidonic acid. These biologically active fatty acids, which are present in very minute quantities in animal tissues, apparently are involved in contraction of smooth muscles, enzyme activity in lipid metabolism, function of the central nervous system, regulation of pulse and blood pressure, function of
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…are hormonelike compounds derived from arachidonic acid. These biologically active fatty acids, which are present in very minute quantities in animal tissues, apparently are involved in contraction of smooth muscles, enzyme activity in lipid metabolism, function of the central nervous system, regulation of pulse and blood pressure, function of
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fatty acid
Essential fatty acids
…acid, and possibly also for arachidonic acid, which is derived from linoleic acid.
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…acid, and possibly also for arachidonic acid, which is derived from linoleic acid.
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lipid
Unsaturated fatty acids
Arachidonic acid (C₂₀) is of particular interest as the precursor of a family of molecules, known as eicosanoids (from Greek eikosi, “twenty”), that includes prostaglandins, thromboxanes, and leukotrienes. These compounds, produced by cells under certain conditions, have potent physiological properties, as explained in the section…
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Arachidonic acid (C₂₀) is of particular interest as the precursor of a family of molecules, known as eicosanoids (from Greek eikosi, “twenty”), that includes prostaglandins, thromboxanes, and leukotrienes. These compounds, produced by cells under certain conditions, have potent physiological properties, as explained in the section…
Read More