Serum-deprivation induces cell death of rat cultured microglia accompaniedwith expression of Bax protein

Expression of Bcl-2 related proteins in rat microglial primary culture was examined. At relative low cell densities, serum deprivation caused cell dea th and nuclei condensation of cultured microglia. Expression of a pro-apopt otic protein, Bar, but not Bcl-2, was increased by the serum deprivation. S B203580, a specific inhibitor of p38(MAPK), prevented both the serum depriv ation-induced Bar expression and microglial death. Immunochemical staining showed that microglia expressing a high level of Bar were subjected to apop tosis-like cell death. These observations suggest that Bar expression under lies the apoptosis of cultured microglia after serum deprivation.