CELLULAR ACCUMULATION OF EXTRAVASATED SERUM-PROTEIN AND DNA FRAGMENTATION FOLLOWING VASOGENIC EDEMA

Accumulation of serum protein has been demonstrated in injured brain c ells following vasogenic brain edema. The present study was conducted to test whether this phenomenon is also observed in apoptotic cells as well as in necrotic cells. Apoptotic cell death has been implicated i n a variety of brain injuries, including ischemia and trauma. Cold inj ury and focal cerebral ischemia-reperfusion were used to induce both v asogenic edema and apoptotic cell death, Evans blue extravasation was used to determine the cellular accumulation of serum albumin, Apoptoti c cell death was evaluated by both morphological alterations and by te rminal deoxynucleotidyl transferase-mediated uridine 5'-triphosphate-b iotin nick end labeling (TUNEL) staining. Evans blue accumulation in c ells was observed not only in the surrounding zone of the lesion after cold injury and in the entire ischemic area after focal ischemia, but was also detected in the regions remote from the primary injury site. Some of these cells demonstrated nuclei fragmentation. TUNEL staining confirmed that apoptosis was induced in the region where apoptotic ce lls were morphologically detected. These observations suggest that acc umulation of the extravasated serum component is accompanied by apopto tic cell death following vasogenic brain edema.