[2][3] If its precursors or diet contains linoleic acid it is formed by biosynthesis and can be deposited in animal fats.

[2][5] Its name derives from the ancient Greek neologism arachis 'peanut', although peanut oil does not contain any arachidonic acid.

[6] Arachidonate is the name of the derived carboxylate anion (conjugate base of the acid), salts, and some esters.

[8] Arachidonic acid for signaling purposes appears to be derived by the action of group IVA cytosolic phospholipase A2 (cPLA2, 85 kDa), whereas inflammatory arachidonic acid is generated by the action of a low-molecular-weight secretory PLA2 (sPLA2, 14-18 kDa).

[2] When incorporated into phospholipids, the omega fatty acids affect cell membrane properties, such as permeability and the activity of enzymes and cell-signaling mechanisms.

[23] There were no adverse effects in adults of using high daily doses (1500 mg) of arachidonic acid on several biomarkers of blood chemistry, immune function, and inflammation.