Prostaglandins and other arachidonic acid metabolites in the middle ear fluids.

Prostaglandins (PGs) and other arachidonic acid (AA) metabolites have been recognized as mediators of inflammation and bone resorption, chemotactic agent to polymorphonuclear leukocytes (PMN), and regulators of inflammatory response. Although assays of some PGs in the middle ear fluid (MEF) were reported, there has been no report on comprehensive assay of PGs and other AA metabolites in MEF. Concentrations of PGs were measured by radioimmunoassay in human MEF. The data on human MEF were analyzed according to age group. In addition, levels of lipoxygenase-products, 5- and 15-hydroxyeicosatetraenoic acid (HETE) and leukotriene (LT)C4 were measured in human MEF. Levels of PGE2 in MEF from human serous otitis media (SOM) were highest in younger age group (below the age of 10) then the levels drop down to lower level in older age group. In human mucoid otitis media (MOM) the levels of PGE2 are lower than SOM in younger age group then become higher than SOM in older age group. Levels of 6-keto-PGF1 alpha were higher in SOM than in MOM overall. The age breakdown of data showed progressive increase in the 6-keto-PGF1 alpha levels with older age group. Levels of TxB2 in SOM were higher than in MOM overall. The age breakdown of SOM data remained almost the same in all the age groups but the MOM data showed lowest levels in 6-10 year-old group and highest in 11-15 year-old group. Concentrations of 15-HETE in human MOM were over two times higher than in SOM. LTC4 levels in MOM were higher than SOM.(ABSTRACT TRUNCATED AT 250 WORDS)