STUDIES OF THE CHOROID-PLEXUS AND ITS ASSOCIATED EPIPLEXUS CELLS IN THE LATERAL VENTRICLES OF RATS FOLLOWING AN EXPOSURE TO A SINGLE NON-PENETRATIVE BLAST

The choroid plexus in rats exhibited ultrastructural changes following a non-penetrative blast, The immunophenotypic features of epiplexus c ells associated with the choroid plexus epithelium were also altered, In rats killed at 1 and 7 days after the blast, the intercellular spac es between the epithelial cells were greatly widened, coupled with the massive eruption and possible extrusion of the apical cytoplasm into the ventricular lumen, Associated with these changes was the passage o f some monocytes/lymphocytes across the epithelium. The incidence of s uch a migratory phenomenon was more frequent in rats killed 7 days aft er the blast, In rats killed 14 days after the blast, the ultrastructu ral changes of the epithelial cells became less pronounced, At 21 and 28 days after the blast, the ultrastructure of the choroid plexus was comparable to that of normal specimens, The immunoreactivity of epiple xus cells in terms of their cell number and staining intensity with th e monoclonal antibodies OX-42, OX-18, OX-6 and ED1 was noticeably augm ented at 7 and 14 days after the blast; this, however subsided at 21 a nd 28 days, It is concluded that the choroid plexus is extremely sensi tive to a blast wave as manifested by its structural alterations and t he vigorous expression of CR3 receptors and MHC antigens by the epiple xus cells, It is suggested that a possible immune response might have been triggered in the cerebrospinal fluid ventricular system following the blast.