Study on neuronal apoptosis induced by hypoxia or traumatic injury in rats

OBJECTIVE: To explore the relationship between neuronal apoptosis and hypoxia or traumatic injury. METHODS: Rat neurons primarily cultured in vitro were treated w ith hypoxia (the hypoxia group) or traumatic injury (the trauma group). The neur onal apoptosis was evaluated with microscope, TUNEL (terminal deoxynucleotidyl t ransferase mediated X-dUTPnick end labeling) staining, flow cytometry, agarose gel electrophoresis and immunohistochemistry RESULTS: Morphological changes of apoptosis appeared in the t reated neurons and the DNA fragmentation showed "ladder" break. The apoptotic index was 10.8% in the hypoxia group and 4.8% in the trauma group, while it was only 1.6% in the control group. The expression of apoptosis-associated genes (c-myc, fas and fasL) increased. CONCLUSIONS: Hypoxia or traumatic injury can induce neuronal ap optosis, and its molecular mechanism is probably related to the expressions of a poptosis-associated genes.