The aim of this study was to determine the type of phospholipase A(2)
(PLA(2)) in nasal fluid and to demonstrate its cellular origin. The co
ncentration of group II PLA(2) was high (591.5 mu g/l) in nasal fluid
compared with serum level (10.8 mu g/l) and the fluid of paranasal sin
uses (10.6 mu g/l). Methacholine stimulated nasal fluid contained only
small amounts (19.1 mu g/l) of group II PLA(2) when the flow of tear
fluid through the nasolacrimal duct was obstructed. Occasional glands
secreting group II PLA(2) were found in nasal and paranasal mucosa by
immunohistochemistry. Lysozyme was found in the majority of mucosal gl
ands. It was concluded that nasal and paranasal mucosal glands contain
group II PLA(2). In nasal fluid, however, PLA(2) is mainly derived fr
om tear fluid.