Hebrews 5:12 (Go to this verse :: Verse pop-up). In context, God tells us one of the purposes of His revelation to mankind. The writer of Hebrews scolds his audience for being dull of hearing (verse 11).
Prostaglandin activity is also intense but short lived, though the symptoms of the resulting inflammation continue for some time after prostaglandin release stops. Mast cells are the main source of prostaglandin synthesis and secretion. Epithelial cells (surface cells of the SKIN and mucous membranes) and platelets also produce as well as respond to prostaglandins.
A mast cell (also known as a mastocyte or a labrocyte) is a type of white blood cell. Specifically, it is a type of granulocyte derived from the myeloid stem cell that is a part of the immune and neuroimmune systems and contains many granules rich in histamine and heparin.