On of these signalingcascades and transcription factors has been reported to be involved in induction of MMP-9 in rat astrocytes [20,24,25]. Moreover, transactivation of receptor tyrosine kinases such as platelet-derived growth factor receptor (PDGFR) by several stimuli has also been implicated in mediating cellular functions of glial cells [29]. More recently, we have demonstrated that LTA induce